Even Pawel can't console Nelly when her architect mother accepts a six months job in Dubai, so the tries to arrange a local alternative: renovating pa' s employer Vinzenz Grieshaber's shabby barn. Another classmate posing as a sheikh canceling the project doesn't work. Philip and Bertie distract Nelly by letting her mind a few weeks a finch fledgling pushed out of the nest by a cuckoo, but hearing she still must live in ten days, she runs away, hidden by Pawel and Pauline. Bertie Heckenbichler even offers to adopt her, but the solution is simpler.

Bertie is stunned and falls from his motorbike when he sees a bear eating at a public picnic table, which doc dismisses as intoxication, but the apprentice doesn't drink and other bear spottings follow, all over Waldau's woodland, where previous and current mayor foolishly check the bee hives as the bear couldn't resist. Nerd Gustav Ott's siting is laughed away by classmates, except fat simpleton Ben Armbruster, who insists to help him convert a shed into a bear trap, which they get trapped in when the bear arrives early. Pawel and Nelly bump into wounded Quintus, who...

To general horror, aggressive behavior, even biting people including a child, is observed over Waldau town from Brezel, vet Hansens's own trusted, ever-friendly longhair dog. Even classmates find it hard to believe Nelly it wasn't him, as the dog makes a threatening appearance on the playground. Bertie can only provide a shaky alibi and must help Philip check out Brezel, who is found healthy and friendly as ever. Pawel ultimately helps Nelly who suspects the new classmate who arrived when the trouble began, Jessie Nagel, and is found to have -but lied about it- a dog ...

Bertie helps Philip test the dogs: their own Brezel easily passes and is released home, but Jessie's confiscated same-breed Iwan remains hostile and too dangerous. Nelly is jealously blamed by Jessie, who even flirtatiously gets Pawel to break into the asylum but they fail to free Iwan. Jessie boldly goes collect him alone, but only runs into trouble.

Pawel's kid sister Paulina finds a tree nest-fallen dormouse and calls it Emil, but they can't care for it. So it goes to Nelly, who is preoccupied with hiding the illicit pet, exhausting enough to be late for each breakfast. She even drags Pawel and mates into detention by failing to stay alert in class. Nelly bickers with her spoiled cousin over who gets which room and whether Greta can go on US exchange program.

Grumpy senior Püringer accuses Pawel of theft, trespassing and so on just for collecting some cherries from a branch hanging on the street, so pa Tomasz Kulka safely grounds the knave, but even landlord Grieshaber comes to the boy's defense against the old fart. Nelly and Jessie turn to brave Pawel and inventive Gustav Ott when they find Püringer sets traps to illegally kill the mole which mess up his lawn, named "Goliath" by the kids, who sneakily manage to catch him. Vet Philip Hansen finally gets integrated in the village's farmers community when Thomas invites ...

Pawel's mother Marie Kulka is having another baby, so father Tomasz tells the knave to stay around more and help out. Jealous of her animal rescue reputation, classmates Kim and Constanze plan to prank Nelly by pretending anonymously over Internet that a dwarf pony is seriously abused. They ignore the stable is actually being used by thieves to hide their loot.

Vet Dr. Philip Hansen diagnoses blind Hanne Seidel's guide dog Lupo incurable due to age. His assistant Bertie Heckenbichler has an instant crush on Hanne, who can't appreciate his looks, but his sweet nature and humor all the more. While Philip spends his day off helping the Kulka family manning the harvester, Pawel and the girls test possible canine successor candidates, to no avail, while regretting a pony was bought by a rich couple who don't even intend it to be ridden. Then it dawns both problems may solve each-other, so Bertie helps them raise cash to invent ...

Vinzenz Grieshaber's youngest calf is ignored by the mother, so will probably die. He nor farmhand Tomasz Kulka nor his son Pawel are impressed by Paulina's eagerness to help raise it by bottle, with some help from Nelly, but she keeps dodging school and sneaking out at night, which Pwel helps cover for anyway. Pregnant mother Maria gets more attention, but herbs seller Wanda Latour gives Paulina a 'natural remedy', actually meant for human babies. Vet Philip Hansen later explains the positive effects of both these plants and 'maternal' tender loving care, while Pawel...

Locals running stands at the town market take objection to newcomer 'hippie gypsy' herbs girl Wanda, especially Elke Deutrich and her husband Hans, who throws a crate at her raven and is attacked by the large bird, whom vet Philip patches up. The next night, her meadow camp and herbs garden are disturbed, so Pawel and friends ditch their first class to help repair and investigate. Town folk reconsider and make up.

Dr. Hansen plans a weekend lake fishing with Nelly and Pawel, whose father Tomasz is persuaded to take time off for once to enjoy father-son quality time. Employer Vinzenz Grieshaber grumbles that's ill-planned in harvest season, but bugged by his wife for domestic chores soon follows with his own tent at some distance. Strangely he catches lots of trout, the others none, so they merge as he brings the fish and shares the men's tent after his mysteriously lands in the lake. Nobody had any idea the culprit, who also scavenges at their scraps at night, is a crocodile ...

The fishing party is back on the farm, but can't forget about the crocodile. Pawel sneakily prepares to go hunt the monster and is picked up by injured Vinzenz Grieshaber, who acts as driver and needs to lean on the knave. A bitten dog is brought in to Bertie by the owner after a lake stroll. Greta and Nelly observe at the lake ex-con big game poacher Roy Freitag, who was hired to hunt the monster by the society which manages the lake. Before doc Hansen can intervene, Tomasz has already rushed to rescue his boy and together they confronted the monster which came on ...

Greta's family and friends prepare a sendoff party as she's about to spend a year in the USA. Boyfriend Jonas Grieshaber hesitates whether to attend, even before his faithful dog Oswald makes a bad fall while courting another St. Bernard dog. It all complicates the elaborate preparations for a party act starring the family pet dogs, despite Bertie's best efforts.