Two married couples decided to have some fun—turning to sinful swinger pleasures. The pleasure turned out to be questionable, and the very next day one of the unfortunate swingers was killed in a hotel room. What’s most interesting is that the murder is blamed on… the expert-analyst Drongo. For him, it is now a matter of honor to find the real killer—saving not only his reputation, but also his freedom. There are many suspects, but Drongo is sure: there isn’t a killer among them—he will appear where he’s least expected.