Anna works at school. She is not just a teacher, but a very talented mathematician. One day, at a meeting with her classmates, Anna finds a murdered man. He was the boy she was once in love with. Without thinking about the consequences, Anna leaves her fingerprints on the crime weapon. She is behind bars. In addition, she is accused of a number of unsolved cases. But Anna is not going to put up with injustice and is ready to prove her innocence. She uses her logic and mathematical knowledge to calculate the real killer. Captain Vershinin helps her in this. What happened causes Anna to look at her life differently, to forget past insults and betrayal.

... | Season 2