A crack team of pilots are selected by the Galaxy Alliance to travel to Planet Arus and uncover the secret of a weapon from ancient times - Voltron! Keith, Lance, Sven, Hunk and Pidge arrive too late, the planet has already been completely devastated by the evil forces of King Zarkon. They engage in battle with Zarkon's general Yurak, only to be captured and thrown into the dungeons on Planet Doom.

Keith and the space explorers take the first steps on their journey to revive Voltron. They find the legendary Royal Castle on the surface of Planet Arus. Inside, they meet Princess Allura and the wise Coran. The Princess declares them to be the planet's new guardians. Together, they unravel the mystery of Voltron's disappearance.

Keith, Lance, Sven, Hunk and Pidge ask for help from the Princess Allura to find Voltron. With guidance from the ghost of her father, King Alfor, they find four of the five keys needed to form Voltron. With no choice, they head into battle with only their robot lions to keep back Doom's soldiers.

The team uncovers the key to the Black Lion, just as King Zarkon's Robeast is about to rain havoc on Planet Arus. Together, they are able to form Voltron's most powerful weapon, the Blazing Sword!

Keith and the team scour the surface of Planet Arus, looking for brave citizens willing to help fight Zarkon. Scared due to the recent attacks, only Princess Allura herself is willing to join Voltron Force. When King Zarkon's best gladiator is turned into a Robeast by Haggar, not even Voltron can stop it. Only if Allura can find a way to help will Arus be saved.

Yurak's attack fleet is soundly defeated by Voltron. Haggar comes up with an evil plan to get Voltron out of King Zarkon's hair for good. She sneaks up to the Voltron Force while they are handing out food to the troubled people of Arus. Haggar isolates Sven from the others and badly wounds him. Without Sven, Keith and the team must face Zarkon's new Robeast without Voltron's power!

After watching the Voltron Force defend her kingdom again and again, Allura is determined to help. However, her Nanny has returned to the Castle of Lions, and is equally determined to keep the Princess out of trouble. When Nanny gets caught up in a raid by King Zarkon, Allura must pilot the Blue Lion to save her!

The mysterious Prince Bocar appears and saves Princess Allura. He seems to be the perfect replacement for Sven as a new pilot for the Blue Lion. But when Lance realizes that Bocar is not what he seems, the evil Prince escapes with the Blue Lion and Allura as his prisoner!

Yurak's fleet shoots down a spaceship over planet Arus. Hunk manages to rescue the pilot, a pretty young slave who escaped from Planet Doom. The Voltron Force is skeptical, but Hunk has faith in her story. That night, the escaped slave breaks into the Castle of Lions' ammunition storage under orders from King Zarkon and plants a deadly bomb!

A girl named Iris was raised as a killing machine by Haggar. Later in Iris teenage years, she travels without Haggar finding the white lion near a small castle in altai.

When Yurak takes a village hostage, the Voltron Force is forced to surrender. A little girl from the village named Tammy sees her mother taken captive along with the others. Trying to get help, she ends up inside the Green Lion. Pidge, in a desperate attempt to save the rest of the team, switches places with Tammy!

After escaping from Planet Nemon, Jai seeks out Princess Allura and the Voltron Force to help save his home. Nemon is under the thumb of Tabor, a nephew of King Zarkon. The evil lord himself has come to celebrate his birthday, but Voltron is coming to crash his party.

Princess Allura's Aunt Orla comes to visit her at the Castle of Lions. Allura's loyal space mice seem to reject Orla, as if sensing something that the others can't. The team becomes suspicious when they spot Haggar's cat attacking the mice, but they can't do anything if the Princess doesn't believe them.

The Voltron Force successfully grounds Yurak's fleet for the last time. King Zarkon is ready to banish Yurak, but then his son, Prince Lotor, returns from his journey of conquest. Prince Lotor turns Yurak into a Robeast, and then challenges Keith to a duel. With Keith away from the team, they are forced to fight Yurak without the help of Voltron!

Princess Allura puts the whole team in jeopardy when she tries to pilot the Black Lion without permission. Seeing no way to make it up to her friends, she surrenders herself to Prince Lotor in exchange for the freedom of Planet Arus. Enchanted by her beauty, Lotor accepts. But Keith and the Voltron Force have a plan of their own.

Arus celebrates the rebuilding of a bridge by reenacting a legend of star-crossed lovers whose devotion to be together let their efforts to unite form the structure. Hunk is all set to perform with Allura after he wins a chance-game to see who will play the male alongside her. However, Lotor attacks for his own personal obsession during the event, and manages to cripple the Yellow Lion once Hunk finally makes it back in after fighting for the lives of both actors.

Zarkon allies himself with King Cova of Pollux, a planet sworn against Arus since they are descendants of an Arusian prince banished for his immorality. His eldest son Avok volunteers to be turned into a Robeast to personally conquer the world he would stand to inherit. Both enemies of Arus plan to betray one another, but Lotor is attracted to Cova's daughter Romelle, who bears a striking resemblance to Allura. Romelle wishes for differences to be settled between the two worlds, and so do the Voltron Force, who approach Pollux in an attempt to prevent war - but they still have to deal with Lotor and the transformed, powerful Avok.

Lotor approaches Haggar's rival Zandra to give him a weapon and is supplied with a potion that will transform plants into monsters, just before Zarkon suffers a terrible disease. Haggar claims the cure is an Arusian fruit. Lotor is reluctant to go, thinking it is trickery, but leaves armed only with his potion when Haggar offers to prove her loyalty by sending armed forces. On Arus, he transforms a group of trees into menaces which terrorize the Voltron Force, intending to take advantage of the situation and capture Allura along with some of the fruit.

Three children discover an unknown castle and choose to look for riches within. Pidge, interested by Coran's story of a similar fortress that held wealth until it was buried so no more wars could be fought among those trying to take its contents, flies out himself and joins the group. Nobody knows it is the work of Haggar's magic until they are trapped in the bell-tower, and the rest of the Voltron Force follow only to be confronted with indestructible fighters - and ships to tow the foundation off when all but Keith are imprisoned as well.

When Pidge's home planet, Balto, is attacked by Zarkon and Lotor's forces, Keith, Lance, Pidge, and Hunk prepare to leave immediately to stop them. When the guys run into trouble in the form of a new Ro-Beast, Keith sends a telepathic message to the Princess. Allura has to decide where her loyalties lie. Should she stay and protect her own home planet, Arus, or should she fly to Balto to save her friends?

Romelle and her fellow captives escape Lotor's prison, but are pursued and forced to crash-land on the frozen world Neve. Both the Voltron Force and her brother Bandor go to rescue her before Lotor arrives, but Allura is nearly tricked by Haggar in disguise. Bandor is tricked and is captured. Lotor orders Allura to give herself up for the lives of her cousins. Keith goes covered in snow as his disguise, but even with that the group still has to think a way around Lotor's attackers to ensure that everyone is actually freed.

Haggar and Lotor send a group of poisoned seeds to Arus which produce handsome plants - which weaken all who pick them for their beauty. Coran and the Voltron Force learn that an antidote is available through a crop of flowers on the magnetically-surrounded Planet Lyra. Allura suggests the underwater-dwelling Blue Lion could fly there since its being used to water would let it through the magnetic field, but she too sickens from a group of the flowers and Lance goes out instead. With the help of a young Lyran named Farla, he tries to get King Mac's permission to harvest some of the plants, but Lotor is waiting with him. He plans to take the plants himself and hold ARus ransom for the sake of their ruler, especially since he knows one of the Voltron Force is dying and another must get past him. Lance loses a duel to him and falls from an infamous wall into a river, but escapes to the Blue Lion, where he must somehow stop Lotor from ruining the crop except for what he'll steal so only he can heal Allura at the cost of Arus - or anyone else.

As Lotor prepares to for another attack on Arus, Allura is forced to work harder on the things she'll be expected to do as a ruler instead of spending leisure-time with the friends she trains with. Trouble occurs when the others in the castle put her safety over her role as a Voltron Force member, and send the other four out without her. They are captured and it is forgotten that her door was locked, so Lotor has nothing to fight against when he attacks her through the window.

Haggar sends a group of small robots disguised as rodents to Arus. Almost everybody is ready to blame the chewed electronics-circuitry on Allura's pets before they themselves are attacked and even more of the castle is damaged. The Voltron Force is forced to battle the creatures who have already ruined the defenses, and another robotic Lotor sends in - without being able to ride the elevators to their Lions to fight.

Zarkon can be seen testing some sort of weapon on Moura, an ally of Arus' now under his control. The Voltron Force set off to investigate. Keith and Lance use the Green Lion's head to approach and disguise themselves as guards. A young man named Haran, who stood against Lotor earlier, reports them. This nearly results in their capture after they find a massive shooting-machine. He is trusted by Lotor for his attempt to see the gun completed in a desperate hope that he will free his people. When the two approach Haran, he reveals that he blames Voltron for their enslavement, since Moura aided them in defense against Zarkon but Voltron was abroad and unable to intervene when Moura was captured. They vainly plead to have him support Voltron in order to see Zarkon's rule overthrown, and are forced to regroup to fight the weapon as well as the powerful Centipede Express Zarkon arrives in.

Haggar uses a spell to grant a powerful robot fighter invisibility. On their way back from the fruit-market, Allura, Lance, Pidge, and Nanny have their carriage forced underwater by it and Allura is nearly captured. The Voltron Force attempt to find a way to defeat their unseen enemy - and even after they bring it into view long enough to note its strengths and weaknesses, they learn the hard way that one of its major benefits is one of their greatest hurdles: water.

Lotor goes to the fume-covered Planet Medusa to arouse and take one of its sleeping inhabitants to fight for him. It turns out to be a monster who can attack with snakes as hair and turn things to stone. The Voltron Force are called away from trying to arrange homes for those orphaned by Zarkon's raid against Arus to fight it. Pidge is forced to eject his struck Green Lion, knocked unconscious, and taken underground by the beast. While the others wonder whether they'll see him again, he is horrified to recover near the creature, but finds the being, Anga, is kind to him. Haggar is determined to turn it evil so it will no longer side against its captors and with their enemy, while Lotor takes advantage of the divided protectors of Arus by sending another menace out. It is up to Pidge to see that no one falls under their power.

Lotor spends his birthday on Tyrus awaiting a shipment of stolen wealth, some of it from Arus' treasury, to deliver to Doom. The Voltron Force notes a distress-call from the neglected ship after an asteroid strikes it and arrive to find the crew out cold, and some of the wealth that they were going to give to charity. Before they can reclaim everything, the ship Lotor sent to collect arrives, forcing four of them to pose as guards and Lance to hide his Red Lion within a golden statue of Lotor. They go to Tyrus planning to attack and take what they can, but are discovered and forced to fight. Lotor plans to celebrate his birthday to ridding himself of his enemies, and Lance must escape where he is imprisoned in a pit with wild cannibals to set the others free.

Haggar creates a Robeast with the ability to exhale flames and emit a magnetic field, which Lotor unleashes on Arus, causing a complete drought. Four of the Lions can take off, but because the Blue Lion uses water as its strength, it cannot fly from the drained lake. Allura must figure out how to fight while grounded, because the others try to hold off the attack as long as they can, but are locked in a suffocating forcefield where they are vulnerable for destruction.

Zarkon decides to have Lotor wed Princess Koral of Demos to unite a similar empire with Doom and she is eager, but Lotor still wants only Allura. Given a sole chance to take what he wishes on his own, he turns to Haggar, who offers him a blade that will put anyone whom it grazes into a coma, mistaken by all others for death. Haggar's cat scrapes Allura with it, and she instantly falls unconscious for hours before appearing to pass away before her friends' eyes. Everyone grieves, but Keith realizes that Lotor would not kill Allura so all must not be as it seems. The four, knowing that Haggar will be responsible for reawakening her after Allura's people bid her goodbye, decide to keep this to themselves as a secret and go ahead with the planned funeral. They try to follow the hearse out, but Haggar causes an accident which makes the driver lose control of the horses. Only Pidge is able to reach it after Lotor has taken it over, and by the time the others fly out to help prepares an attack with Haggar. Pidge is determined to do whatever it takes to save Allura, but thanks to Haggar it may cost someone else's life...

When Zarkon denies Lotor the power of his whole army to attack Arus, Lotor tries to take his power from him by besting him in combat, but fails and acts humble enough to have his life spared. Haggar convinces them to put aside their personal disagreement for the moment since she reveals she's built a Robeast with a frame slightly resembling Voltron's and directed by a robot pilot to conquer Arus. Arus' defense-system is destroyed just after it shows what approaches, and the Voltron Force discover their opponent will not easily be beaten. Voltron is forced to fight while growing weaker and weaker as he is damaged by the strong machine, and the Blue Lion that is the main power-source as his Right Leg faces possible destruction.

With the Blue Lion down, Zarkon encourages Lotor to attack Arus right away. After cryptic message from King Alfor, Keith decides what the Voltron force needs is more training. During the training exercises, Hunk fails to keep the Yellow Lion attached to the rest of Voltron. He starts to question his worth to the team. When the latest Ro-Beast attacks, Hunk asks Keith if he can lead the attack in order to prove himself to the rest of the team.

Haggar creates many miniature-robots disguised as tadpoles to invade Arus since they will thrive in water which Voltron would otherwise not wish to enter. Two siblings collect some to study at home with Pidge's help, and he takes some himself. That night, a group of mutant amphibian-like creatures attack a ship and the children's home. Though they easily destroy the ones in the castle, the Voltron Force's attempt to destroy those out at sea proves more than the usual challenge when a larger robot arrives as well, and damages the Green Lion so Voltron also leaks when formed.

Lotor causes a near-hurricane to strike on Arus, forcing the Voltron Force to go out and round up civilians to shelter in the castle. One boy refuses to go without giving a reason. Since he holds a rabbit, Pidge believes he has stolen it, especially since he says he found it in a trap, which are illegal on Arus. Pidge attempts to fight him then starts to pursue him into the woods - until his own ankle is caught in a snare. The boy, Tommy, releases him before they witness Zarkon's robots poaching. Pidge isn't strong enough to return on foot and when he tries to relay the news through radio, an "earthquake" like one seen earlier destroys it. The divide created by the storm is occupied by something, and the two journey down to examine it. Lotor discovers them and reveals his giant bomb of enough force to destroy all of Arus (except Allura, whom he secretly plans to evacuate). They have no way to contact the rest of the Voltron Force, but to let anyone else know it exists, must escape where Lotor has them bound to the activated weapon.

Arus is set to host the Space Olympics as they are thriving thanks to Voltron. Zarkon and Lotor are too jealous to participate, but plan to take advantage of Haggar's offer to bring down Arus. They place a small robot in the earth-mover that the Voltron Force is using to construct the facilities, planning to use it to destroy the buildings and then the planet. The children helping them are taken hostage within the machine. The Voltron Force are forced to stop the mechanical rampage while keeping themselves and their friends alive as well.

Zarkon blames Lotor for Voltron's continued victories, and commands that he himself, not a robot, take down the Voltron Force. He has Haggar create a stronger and equally-wise duplicate of himself instead, which he sends to Arus. When a Robeast's forcefield disables both the castle's and the Lions' power, Keith swims out to set up a mine to disable it. The clone arrives to fight him with surprising skill. The others hurry to prepare the limited technology they have for him to return, but don't know that he is locked in single combat in which he will have to win before returning to form Voltron, the only thing that will ruin the machine.

While visiting the academy where Lotor trained, he and Zarkon witness a pilot nearly strike them twice while landing. They are eager to meet the daring pilot, Carp, and approach him though he is disliked by the trainer, Morgil. They decide he should be the one to operate Haggar's latest Robeast to crush Voltron. Carp stuns the Voltron Force when he continues to increase his speed until they cannot keep up, even when they use the Lion-heads to aim for him. While he has seen this limitation, they have little time to figure out another way to successfully oppose him when he returns.

Lotor sends Haggar's small human-looking "Red Beret" robots to frighten the Arusians. As planned, the people soon fall into panic, to the point where they blame Allura for not being able to protect them. Lance and Pidge note the volcano that the beings landed near looks as though something is being dug out of it. However, they are called back to the others to restore order before they can discover what is is. They're just in time, though, to see the Red Berets strike by throwing transformed volcanic dust on the Black Lion and paralyzing it. Though this is their last attack, the Robeast following them will make short work of the others without Voltron there to stop them.

Haggar locates and takes control of the Omega Comet, a legendary black-hole-like structure which crushes and destroys anything in its path, and sends it for Arus. Though Voltron redirected it once after a decade of trying, the Voltron Force are forced to race against time to move it themselves after they get Romelle's warning. Seeing Allura's cousin's loyalty to them, Lotor mentions that a certain control-function will help them in front of Romelle, and she relays the information to them. But it was a trap Lotor had her lure them into, and they crash-land and are stranded upon the comet without power. The Galaxy Alliance can send no reinforcements thanks to Zarkon's fighting. But Bandor goes against orders to stop guarding the power-supply he was posted in front of to repay his comrades. The Voltron Force cannot escape, and conclude that Bandor must use his arsenal to strike the comet away from Arus - though they know it means self-sacrifice.

Bandor remains near the Omega Comet, desperately trying to contact the Voltron Force that everyone believes are lost, with no success. Coran, supporting him, is forced to stand alone with his men against Lotor's latest raid on Arus. Coran made it so Bandor's ship, attached to Voltron, actually gains strength through the connection. The tie, however, severs when one of Zarkon's attacking fighters strikes it, resulting in the Omega Comet shooting out of control and Bandor's crew tumbling off alone. The Voltron Force approach the end of the universe, where a mysterious voice offers that they can now enter a place of peace and contentment, but as the price would no longer be able to support Arus...

The one who approaches Romelle after her being forced into the Pit of Skulls is a young, wild-eyed man who warns her of the approaching guards that come down to ensure she is finished, and helps her into a passageway through a cave but then vehemently bids her leave him. She is able to identify him as Sven, but the former pilot of the Blue Lion has lost his faith in himself, feeling remorse over his defeat by Haggar and his inability to aid Planet Ebb when it was attacked when he was hospitalized, and is nearly mad with grief after witnessing so many brutalities every day. Romelle tries to convince Sven to help her get off Doom and contact the Voltron Force so she can return to and defend Pollux as only she knows how, with the help of a group of slaves who are desperate for their own freedom and could be what they need to help them escape...

Lotor sets up on the Sand Planet, with Haggar's plans to transform the thriving, small, pure natives into robotically-charged menaces. Coran's friend, Professor Sarwa, contacts the Voltron Force with the news and calls them to come help just before he disappears on his study-tour there. They meet him and are charmed by the amusing Sand People. But Lotor arrives and uses nature against them to prevent them from taking a group hostage, and transforming them to fight his enemies as well.

Zarkon orders Lotor to conquer a world he has just discovered, knowing that Voltron will arrive with the intention of freeing the people that will be enslaved there. Haggar plans to increase the planet's gravity so that Voltron's actions will be ineffective against her own robotic menace. Four young children are more determined to see their planet freed by whatever way they can and have more belief in Voltron than their parents. They try to take Lotor prisoner but are captured instead. They are used by Voltron's enemies to let the Voltron Force know of the situation after all. However, they are powerless to warn them of the danger that will be faced during the planned rescue.

Yadle, an unattended colony-planet of Zarkon's, declares itself independent and prepares to celebrate along with its allies, the Voltron Force. Haggar creates a Voltron look-alike to subdue its people with Lotor's guards before it will be used to attack the real robot. A young friend named Bobby goes to guide the Voltron Force to Yadle to get through Zarkon's magnetic field. However, they have yet to be warned that they are awaited by a robot that has all their powers and the ability to know what maneuvers they will perform even before they carry them out.

Sven and Romelle learn that Zarkon plans to use a large quantity of lazon for something, so go to spy on him. He selects his five-hundred strongest Robeasts to be sent off to be energized with lazon. The two are able to warn the Voltron Force of this, but in order to prevent the army from being launched against Arus and its supporters, Sven disguises himself as one of the creatures and stows aboard the transport-ship as the only hope of discovering where the factory-base is located.

The space mice are in training for their next encounter with Haggar's blue cat. Pidge gets the idea to even build them their own version of a Voltron Lion. Haggar brings to Arus her newest Ro-Beast, which creates a canyon in the ground. The Voltron Force can't see it, because its hiding in the canyon walls. Suddenly, the Ro-Beast shoots out chains from both sides and captures Voltron. Now it is up to the mice to try and help Voltron save the day.

When Allura, Keith, and Coran call together the rulers of Pollux, Titus, Torus, Yadle, and another planet to plot extended defense against Zarkon, he makes an appeal to the Drule Empire which Doom is a distant part of for support. Without knowing he was rejected, he has Haggar set up a group of impostors as an ally's ambassador-crew and "attacks" them when they land on Arus. During the resulting scouting-mission, Keith invites Allura to use the Black Lion. But Lotor has rigged it to fail and, after a crash, she is forced to run from his last-chance interception and Keith is injured when defending her. Voltron is needed to defeat Haggar's attack, denying Keith any time to recover.

When Allura loses contact on Chemara's moon Cryo while racing back to the castle with the others, a young humble Arusian man named Garrett rescues her. Coran eventually recognizes him as his long-lost son by a pendant he wears, and the Voltron Force welcome him and are set to let him pilot the Blue Lion. But none of them are aware that he is a spy from Haggar, until he locks all who can help the five out of the control-room and works them into a trap where they will be attacked by the stolen Polsar Canon as well as a typical robot enemy.

The Voltron Force decide to disengage at the moment the Polsar Canon will be fired at them (along with the robot they are fighting) so that their enemies will mistake it for a fatal detonation, and end up crashing in separate locations. Those in the castle that are trying to force out Garrett are unsure whether anyone is actually alive so do what they can to defend themselves. Lotor goes back on his word to the clone to let him lead a population of his own on Arus, so Garrett is determined to conquer the planet himself. The Voltron Force eventually find each other and learned what happened to Coran's actual son. However, since the Blue Lion is damaged, they seem about to be forced to try to destroy the solar-powered canon by night without the full power of Voltron.

Zarkon has Lotor arrested for losing battle after battle against Voltron, and attempts to lead a fight himself. But the Voltron Force succeeds in beating him back before he can topple the Polstar Canon. They actually intend to use this canon to boost them out of Arus' orbit to Doom. In this way they can destroy Zarkon's arsenal there to free the enslaved. But Zarkon and Lotor both get a surprise when the Drule Empire hears of the defeat. They're willing to bet that Lotor could do better than Zarkon, and tell him to arrest Zarkon in the same manner when he returns home. Lotor decides it will be a win-win situation if he forces Zarkon to pilot a giant robot to do battle when Voltron arrives...

Voltron is determined to stop Zarkon's reign of terror - which Lotor, who has claimed himself King of Doom, plans to carry on himself. Sven, Romelle, and their group of followers are just as set on freeing those they witnessed suffering in slavery. They work to slowly destroy everything that has been used to torture them. But though their enemies find themselves divided from within on almost every level, the Voltron Force still must face a major threat: Zarkon is eager to defeat them, even in the humiliating circumstances of being forced to fly a large robot likeness ...

The Voltron Force and their allies prepare to take down Castle Doom, the last of Lotor's defenses. But Voltron is nearly destroyed before they can actually land, until Coran pilots the Castle of Lions in its spaceship form to support them. With Haggar having parted ways with him, Lotor's downfall seems definite. But in trying to make certain that his tyranny will never rise again, Sven is drawn into a trap. He is held at ransom, to the horror of all his friends, and has the seemingly impossible job of trying to find a way to stop Lotor from melting their beloved robot...