It's the last day of school and Alessio, together with two buddies, set off the alarm for a bomb at school in order to throw water balloons at everyone. The three friends are planning a trip around Europe by train. First rule: There are no rules.

Cetinka's Polish specialty, an onion and mustard soup, doesn't go down well with the Martini family.

Alessio flunks out and his parents aren't letting him go on the trip he's been planning for a year. He decides to take things into his own hands.

The rehearsal for Lorenzo's funeral gets interrupted by Manara and Toscani who want to question Scudieri, the bass drum player. Meanwhile, Lara is trying not to explode with anger about Manara's handling of Ginevra Rosmini.

The shower is finally getting fixed by a plumber who's dreaming of having his own business, which makes Libero kind of nervous. And Aunt Alice is having a hard time with her boyfriend.

Wanting to rest, Alessio finds an old kayak on the beach and falls asleep in it. What could possibly happen?

Sardi wants to comfort Toscani after he'd been punched in the face by the bass drum player. Manara wonders where people go in the evening, and Lara, after seeing the Commissioner in a car talking to Ginevra, goes home and confides in her Aunt about why she can't stand him.

Some money disappears from Libero's pocket and he immediately suspects Cetinka's boyfriend. Lele doesn't think he should be accusing anyone without proof, and Libero makes a crack about old people. In order to understand the double-entendre, you need to know that a stufa is a heater and that stufare is to be a bore.

Alessio is stuck at the beach because his scooter has a flat tire. In order to get it fixed he looks for work at the beach club where he had fallen asleep the night before.

At the end of his day's work, Alessio wrecks the truck he'd loaded, and has to stay on at the beach club for ten more days of work to pay for the damages.

Lara decides to question the medical examiner Ginevra, the last person to have seen the victim alive. Manara had a different idea about how to handle his witness.

At the beach club Alessio does a little of everything: he waits tables, leads an exercise session on the beach, and takes care of the deliveries. He also meets someone!

At work, Lele is preoccupied with the Cetinka problem, but then his superior gives him new things to worry about. And if that weren't enough, Grandpa Libero calls him about more missing money and more suspicions, pointing to Giacinto of course.

With the information given by Ginevra, Luca and Lara go to the pharmacy to find out about recent sales of two drugs. When combined, the drugs are fatally poisonous. That same day the funeral takes place and the whole town is there. Manara takes advantage of this to look for new suspects.

An important new element in the investigation comes into play: some romantic letters found at the victim's house. Lara is comparing the handwriting to that of the note found next to his dead body.