Kumar, a thief by profession poses as the son of Raja Bahadur Singh to accept an invitation to the island of Sir John Locksley. The guests include K.P.W. Iyengar aka Romeo, Dr. Dubari, Colonel Columbus, and Countess Sylvia Rasmussen. A stunned Kumar finds out that all of these invitees are master criminals. Kumar's guise does not fool anyone, nevertheless Sir John permits him to stay on. The reason why John has invited them is to find a successor to take his place as he is dying of cancer. He fe...