Matteo tells the boys the story of Marcello Rossi and Angeletta: a countess named Isabella is the girl's grandmother. Romeo now wants to find out everything and secretly follows Rossi to a castle where the Ice Queen, as Isabella is called by the others, lives.

Angeletta's greatest wish is to meet her grandmother, the Countess Isabella Montovani, before her serious illness progresses. The Black Brothers therefore drive Angeletta to the castle in a wooden cart. Rejected by the security guard, they climb over the wall. They are discovered and there is a chase in the castle courtyard.

Angeletta's condition is deteriorating rapidly. The so-called Ice Queen Montovani wants nothing to do with her granddaughter. Even asking chimney sweep Rossi is useless. The Black Brothers therefore clog the chimneys of Montovani Castle. They want to force the Countess to stay in touch with Angeletta.