Roger Stanford is a chemist whose uncle, David, has taken over a business that his parents built and his aunt controls. David plans to sell the business to a conglomerate, and uses dirty tricks to get Roger to go along. Roger double crosses and murders his uncle with a booby trapped box of cigars rigged to explode as he drives through the mountains with his chauffeur. Everett Logan, the next-in-line vice president whom Roger discredits as part of the offshoot of the murder, so Roger can take over the company. David's secretary is romantically involved with Roger. Final clue/twist: Columbo tricks Roger into incriminating himself by having him believe the fateful accident was a result of treacherous driving conditions rather than Roger's bomb. Columbo shows Roger a damaged but intact box of cigars and tells him it came from the death scene. Along with Everett, they take a cable car up the mountain. Roger, thinking they are the booby- trapped cigars he had planted, becomes unhinged. He screams at Columbo to get rid of the box because it is about to explode. Columbo reveals that the box is not from the death scene, that he had just got it and scuffed it up to look like it had been. Realizing he has been tricked, Roger can only laugh hysterically. Directed by: Edward M. Abroms. Story by: Lester Pine, Tina Pine, Jackson Gillis.