Former children of the orphanage came to the "alumni meeting". They are happy to see each other, remember the past, but notice that their favorite teacher, whom everyone called Mama, did not come to the meeting.

Four former pupils decide not to sit idly by, but to find out why this happened. Right from the feast they go to Mom's home where they meet a man who says that the woman does not live here. The heroes undertake an investigation and find out that in the house where Mama lived, almost all the apartments were sold to a company, which is backed by an odious sect, and the educator herself disappeared.