Khan undergoes some pangs of conscience when a former British agent stands accused of diamond robbery and the evidence is overwhelming. The man saved once Khan's life.

The killing of Khan's friend, a physician, is linked to an international crime syndicate, dealing in gambling and narcotics which appears to be moving into California. During a Hong Kong-San Francisco telephone call, both caller and recipient are shot dead and Khan discovers that the key to the mystery lies with a man who returns to San Francisco for his daughter's wedding.

Khan has only 24 hours to find an oil heiress who is being held for a huge ransom. A woman hires Khan when her daughter is kidnapped and a $ 300.000 demanded.