Karl discovers that a fossil has been taken from his collection. He accuses Heidi and Peter—but the culprit turns out to be someone else.

Heidi and her grandfather ride a sled through the valley — it’s her first time, and she loves it! Peter, meanwhile, is having a rough time in class, and the teacher isn’t going easy on any of the students today.

Peter and Heidi are shocked to see that Karl, Theresa, and Willi have taken over their tree house. But then Heidi hatches a plan to get them out…

When Peter plans to climb a mountain to harvest snail clover, he leaves Heidi behind to look after the goats. But things don’t exactly go as planned…

The treasure hunt can begin! The two teams have been given different clues by Karl, and are now setting out on the adventure.

Heidi and Peter manage to trick Karl and Theresa into telling them where Peter’s treasure chest is hidden. They bring the chest back to the tree house. But someone has been spying on them!

Heidi runs to her grandfather in tears because she can't believe what people are saying about him. Is he really to blame for the death of Tobias, Heidi's father?

Heidi now learns the entire story from her grandfather about her father’s devastating accident. She comforts him, and promises that she will always stay with him.

In Hamburg's fourteenth precinct, a new colleague joins the police force and a new case is presented: a mysterious accident at a construction site.

Ben notices a few odd circumstances surrounding the death of Jannik Sternberg, while the cops at the station continue to try to impress Nicole, their new colleague.

Too many things about Jannik Sternberg's death seem odd, especially when the colleagues find out that this isn't the first "accident" at the construction site.

In this episode, the police find more evidence that Jannik's brother-in-law, Mr. Nagel, may have been involved with his death.

The officers investigate an unlikely break-in as the case of Jannik Sternberg becomes increasingly more suspicious.

The construction site where Jannik Sternberg fell to his death comes under scrutiny. At the station, Dirk and Lothar realize that Nicki might need a bit more supervision.

Jannik Sternberg's boss offers his widow a payoff, and in return his widow offers the police evidence of Sternberg's apparent suicide.