The case for Kwiatkowski. African mask

Kwiatkowski is a real detective who loves Carpenter's milk and chewing gum. Instead of homework, he has night ambushes, instead of children's entertainment - dangerous adventures. Any of the most intricate crimes is doomed to failure if he gets involved.
Giovanni, the owner of the best ice cream parlor, is in trouble: a coffee machine suddenly exploded, and then the ice cream maker broke. And all this after the appearance in the cafe of a mysterious African mask. Did the dark forces decide to take revenge on Giovanni for something? Kwiatkowski does not believe in superstitions and begins a dangerous investigation.