Salarymen Uozo and his friend Kosaku plan to climb a mountain. A few days before they are due to start, Kosaku confesses that he has had a fling with a married woman, with whom he is now madly in love, but she has just dumped him. The rope breaks during the climb, killing Kosaku. Was the rope faulty, or did Kosaku plan to kill himself ? The rope manufacturer pressures Uozo towards the suicide theory, but Uozo stands firm. Who will back down ?