Andrzej (Leon Niemczyk) and Krystyna (Jolanta Umecka) are driving in their Peugeot 403 to a lake to go sailing when they come upon a young man (Zygmunt Malanowicz) hitchhiking in the middle of the road. After nearly hitting him, Andrzej invites the young man along. When they arrive at the lake, instead of leaving the young man behind, Andrzej invites him to go sailing with them. The young man accepts the offer, and, not knowing much about sailing, must learn many hard lessons from Andrzej.