Summer 1943. In the district of the Kursk arc on the order of Rate the important area of railway is built strategically. To destroy an object, Germans pelt the group of saboteurs in our rear. One of them, German by name Elsa, the fighters of СМЕРШ of lieutenant Sergey Соболя succeed to take living. But interrogations give nothing. To educe the agents and betrayers, involved in injury of railway, police operatives think of an ingenious plan. Sable arranges escape to Elsa. So a chance appears, that she will show out смершевцев on the accomplices. That happened then, became a frightful surprise for all participants of operation.