A young boy tells Captain Midnight about the strange and abusive behavior of his father, a gem expert preparing to cut a million dollar diamond. With the aid of Tut's new invention, a miniature television camera and transmitter, Captain Midnight learns that the boy's father has been kidnapped and a double has been put in his place. The plan is to steal the diamond when it is delivered for cutting. Captain Midnight arranges for the release of the boy's father and the apprehension of the criminals behind the proposed theft.