Former government assassin Jonathan Hemlock (Clint Eastwood) now devotes his time to teaching and collecting paintings, but his quiet life is interrupted when he is persuaded by his former employers work for them again. Hemlock has to join a crew of explorers (George Kennedy, Jack Cassidy) on a trip up the Eiger, a treacherous Swiss mountain. Hemlock must simultaneously determine which of his fellow climbers is a Soviet spy, kill his target and scale the deadly peak.