Evgeniy Okhotnikov’s bodyguard carries out an honorable order - he protects the famous developer of atomic weapons Anatoly Stepanovich Zubchenko, whose life has already been attempted more than once. Well, the work is familiar and for such a smart girl like Zhenya, sometimes boring. However, everything changes when unknown attackers kidnap the client’s only son, Yegor, demanding an exorbitant sum for him. The wife of the ward also got it: the villains splashed sulfuric acid in the face of the unfortunate woman. Okhotnikova has no choice but to take on the functions of a private detective. Investigating the disappearance of a young man, Zhenya has to rummage through the affairs of long-ago days, which involuntarily cast a shadow not only on his scientist father, but also on the entire glorious Zubchenko family. It turns out that quite a few people want to get even with the venerable academician and his family...