Marathon for the Three Graces (from the series «Three friends in search of money and happiness»)

Katya, Zhanna, and Irina are cheerful middle-aged friends. They don't have secrets between them, they trust and help each other in trouble. They don't need to look for trouble, it's the trouble that finds them.

At a cafe, a bizarre couple gets the friends' attention: the woman secretly passes an envelope to the man. Several minutes later, they spot the same man on the bathroom floor, shot. Before the police came, not only did Katya leave her fingerprints on the gun, but she also took the dead man's envelope with money and photos. All that is left to do for the girls now is to investigate for themselves before Katya ends up in jail for the murder. The dead man turns out to be a private detective who blackmailed his targets for hush money. Having gone through his last dossiers, the friends are trying to find out the victim of the blackmailer who was the most afraid of disclosure.