While the whole country is watching the 1980 Olympics, strange things are happening at one summer camp on the Volga river. Children mysteriously disappear at night, and then return - but not at all the same as before. Carried away by summer freedom and each other, the counselors do not notice how scary urban myths come to life, and the camp leadership pretends that everything is in order. Two boys take it upon themselves to figure out the mysteries. To begin with, they have to figure out if there is at least someone left in the camp who can be trusted.