Henning finds a potential lead regarding the runaway boy's identity, while Petri turns up at his former workplace yet again – this time armed.

In this Christmas comedy, Academy Award-winning actor Christoph Waltz plays a pet shop owner who generally prefers animals to people. Recently divorced, he is still very attached to his ex-wife – who lives right across the hall from him.

Tarek and Nico talk about what it takes to run a business. It turns out that Nico is good at fixing bicycles, just like his aunt! And suddenly, Yara arrives back at her shop.

Katja and Dirk arrive in time to stop Mr. Petri's madness and bring him in to the station. Meanwhile, Lothar finds out the truth about their supervisor.

Konstantin, the new temp worker at the pet store, wonders why he's even needed considering how little money the store is making. Meanwhile, owner Johannes uses the store's problems to try to bring his ex-wife Marion – who also happens to be his neighbor – back into his life.

While Dirk bonds with the young runaway, Katja figures out what actually happened at the Harms company.

Yara is surprised to see her nephew Nico at her shop, since she didn't realize he was in Germany. Nico, Tarek, and Yara decide to go have a meal at Tarek's restaurant and tell each other what happened.

Petri's colleague is arrested, and Petri and his wife make amends. It's time for Julius, the young runaway, to say goodbye to Harry and go home – but Dirk has one last surprise.

Johannes asks his new employee, a psychology student, about love and relationships – but doesn't particularly like the answer he gets in return.

When Marion comes by to help Johannes with his taxes, he finds out she's met someone else – news he doesn't deal with particularly well.

Over a meal at Tarek's restaurant, Nico and Yara talk about home and homesickness. Then Yara explains why she went to Switzerland.

To earn some money and help out his injured employee, Johannes visits several families pretending to be Saint Nicholas – and ends up making quite an impression.

Nico explains that he wants to change some things in his life. In particular, he is not happy being a law student.

Sascha reveals to Johannes, who is dressed as Saint Nicholas, that his parents are on the verge of separation. Later, Johannes spies on Marion and her new boyfriend at the Christmas market.

While Johannes spies on his ex-wife and her new boyfriend at the Christmas market, Sascha confronts him about the promises he made.