S1, E4: Amosov, meets the waiter, whom Lena identified as the killer of his brother. He manages to get his fingerprints and give them to the laboratory. The director of the restaurant calls Amosov and says that the waiter has asked for leave and left. Amosov offers to help and resolve the issue with Polozkov, and in return asks Lena to go to the waiter's apartment together.