In the territorial waters of the USSR, the team of a border ship recorded a deviation from the agreed course of a foreign vessel. During the inspection of the incident, it turns out that the offending vessel threw an object overboard. The border guards, with the help of a journalist assigned to them, establish that this is a radio beacon belonging to one of the Western intelligence services. The commander of the border ship Chaika, realistically assessing the threat that such a transmitting device poses to the country's defense, decides to prevent its removal, for which he simulates a breakdown of the ship...