Former police officer John Scottie Ferguson is a private detective in San Francisco. He has suffered from acrophobia since the death of his fellow officer who crashed to the ground. His dizziness forced him to give up his business. His old friend, Gavin Elster, asks him to follow his wife, Madeleine who feels possessed by a spirit and tries to commit suicide. Scottie quickly falls in love with Madeleine whom he saved once from drowning. But he is unable to save her from a fall due to his vertigo. Feeling guilty following this accident, he sinks into despair, until he discovers an employee in a hotel, Judy Barton, who is an amazing lookalike of Madeleine…