The crew of the HMAS Hammersley uncover a terrorist plot to assassinate a senior United States official. Kate has some doubts about the Hammersley's new popular crew-mate, a war hero who holds a dark secret.

The new CO of the HMAS Hammersley goes to extreme lengths to capture a violent crocodile poaching gang. A serious conflict of interest threatens the romance between Mike and Kate. A drunken brawl in a foreign port leads to 2 Dads facing a court martial.

The crew of the HMAS Hammersley launch a daring raid to recover a cargo of stolen uranium from armed terrorists. When Dutchy injures Kate during a boarding party, she questions his professionalism. Mike's godson is taken hostage by smugglers.

The crew of the HMAS Hammersley pursue a man accused of kidnapping his child during a custody dispute. While attempting to free the child, Kate is taken hostage, and she and Mike discover things are not all plain sailing when they start making plans for their future life.

The HMAS Hammersley has to stop for repairs after its propeller is caught in a fishing net, which also contains the corpse of a man, later identified as never missing-declared Edward 'Teddy' Pritchard. While waiting, the boys want to fish, the girls to hike, so everyone visits an officially uninhabited, idyllic island. On it they find Peter's ecologist paradise commune. Handsome member Sean wins the favor of Bomber, who rudely rejects all attentions from again utterly confided Robert. 2Dads nearly drowning in a toxic vapors swamp's quicksand is only the first scary ...

The crew's fishing fun is ruined by an abnormally low-flying Cessna owned by cattle rancher Jim Mathieson. Shortly after, they find wreckage of its crash and a single, badly wounded survivor, identified as Karl Butherworth. He was one of three escaped convict murderers who kidnapped the owner to fly them to Papua new Guinea and may be at large. Pressed for medical equipment, the ship sails to isolated island Tapoa. Charge leads a landing party to Dr. Nadal's tiny hospital, only to find him shot and be attacked by another escapee, overpowered thanks to Dutchy's combat ...

Once more, the Hammersly boards incorrigible Asian fish poacher 'hannibal's trawler, but has to let him go for lack of proof. RO, who insisted to come along after a previous incident, is bitten by the ship's dog and fears rabies. Swain has to appease him by prescribing a tranquilizer, but he takes an overdose and is unusually susceptible to side-effects, in this case delusions and sleepwalking, making him jump overboard. The ship back-trails, but RO has already been rescued by Hannibal, who reduces him to slavish fishery laborer and refuses medical treatment after his...

The Hammersley picks up a floating cooler full with recently harvested human organs, next exhausted, confused illegal refugees on Asian smuggler Putra's boat. Unable to prove organ trade and probably theft, given blood test kits and cards, they find clues to set a trap for the presumed mastermind, American Wessel Berkelman. Swain is left with apprentice Bird and the refugees, but they are surprised and overpowered by Berkelman's armed crew. His 'doctor' is accidentally shot, so Swain is forced to take over.

A Hammersley boarding party finds a boat suspected of illegal fishing is actually Australian. Frustrated, the XO orders an illegal search which reveals a presumable smuggled Asian whiskey cargo. When the crew takes careless Kate hostage, Dutchy freezes and orders RO to let them escape with their RANavy weapons. Captain Stenlake is desperately determined to retrieve the guns and arrest the smugglers. In the process, Dutchy repeatedly takes excessive risks, even against explicit orders, especially when puzzled Kate is at risk. 2Dads' attempt to convince RO of his hero ...

The crew's shore leave is cut short to help with floods in Carpentaria bay. On the way, the Hammersley responds to an SOS to rescue drowning passengers from cattle transport ship Olympus, which was hijacked to steal and sell its cargo. RO is punished with menial 'light duties' for boarding without reporting his recent appendectomy. Next they find the ship, liberate the captured crew and search for the cattle and thieves. Dutchy is the big hero again, RO and 2Dads the rascals. Bird rightly predicts trouble after mutually recognizing her ex Darryl, whom she dumped for ...

2dads goes missing while on a reef dive, charge doesn't believe the theory of a shark attack and when they find american dollars aboard a north korean ship in the search area suspicions are aroused leading to the discovery of a heroin smuggling operation and the safe return of 2dads.

The HMAS Hammersley is delivering medical supplies to minor islands off the New Guinea coast. After a live grenade explosion wounds local chief Suil's son Tiken, who risks being blinded, Swain stays behind, with Dutchy as protection, to assist the only nurse, Sarah Denton, who tests his marital fidelity. On another island, Bird contracts a mysterious illness, soon leading to complete paralysis, but no medical helicopter is available. Suil's hothead local rivals use violence, forcing Dutchy to lead a perilous jungle flight.

Leo is delighted that his smarter, slicker cahoot in youthful mischief, Fraser, has joined the Navy, is assigned as trainee to RO, impresses everybody and gets painfully rough pokers debtors off ma, handled Leo's back. The HMAS Hammersley suffers suspiciously many errors and flawed clue in the chase for masked Australian pirates who board yachts, mainly to steal expensive equipment. Leo finds Fraser never stopped scamming and may have teamed up with criminals.

The HMS Hammersley chases a fleet of boats from which the crew catch fish for live sale to aquarium lovers. Swain works out they must be using greatly diluted poison. Bomber messes up completely, even gets the XO wounded, yet wines about her promotion chances. 2Dads arranges she gets a chance to prove herself 'commanding' him and the XO aboard a boat where poison was found. They get captured and seem pawns between a human captain and his violent rival.

The Hammersley finds Lara Strauss, floating after her yacht was wrecked, and starts searching for her missing husband Martin, whose brother Karl turns up. It soon becomes clear they were involved in a gold robbery, and probably so is ill-reputed salvage entrepreneur Alby Dumas. RO has endless trouble with the communication equipment. Dutchy is injured while diving for the wreck. 2Dads' forbidden sexual affair with Bomber is found out aboard, she promises to leave the ship, or even the Navy.

The crew of the HMAS Hammersley race to save Mike's life after he has been taken prisoner by cocaine traffickers.