His half-brother, Rick (Gary Conway), only wants to spend money on various hobbies and interests like sports and fast cars and has also been married several times.
When Rick gets tired of Adrian's indulgences, he announces his decision to sell the land to mass producers of cheap, profitable wines.
Stone is also the mastermind of a publicity stunt that involves fabricating death threats against Hayward, to promote his tough stance against crime.
Final clue/twist: Hayward, realizing that Columbo is coming closer to solving the murder, stages a phony assassination attempt on himself.
When the police express shock at the brazenness of the alleged shooter, he feigns outrage at them doubting his word, and demands that the bullet be removed from the wall and analyzed.
He explains that after Hayward had been alone in the room (a time when he ostensibly was making phone calls), Columbo had searched it and found the hole in the window and the bullet in the wall.
Keppel's more lucrative sideline is blackmail: he takes pictures of married clients with attractive women he hired to get them in compromising positions.
Subliminal photos of a refreshing drink are inserted into the film, which lure Norris out of the screening room, and Keppel shoots him in the lobby.
He arranges to splice into a film subliminal cuts of images of Columbo closely searching areas where the murder weapon must be.
While Greenleaf pretends to get drunk at a nearby bar, calling a lot of attention to himself, and even stages a DUI fender-bender accident to establish an alibi, Kane walks into Mallory's apartment and shoots him.
When Dr. Howard Nicholson (Lew Ayres) threatens to expose Neil Cahill (Robert Walker Jr.) for plagiarizing a paper from a recently deceased scientist, Neil's father, Dr. Marshall Cahill (José Ferrer), director of a high-tech Pentagon think tank, kills Nicholson to protect his son's reputation.
His zealous wife Edna (Ida Lupino) can prove he committed statutory rape with one of his backup singers, Maryann, when she was a minor.
He hides the parachute and lies down near the burning plane wreckage, making it seem like he was thrown clear in a tragic crash caused by flying through bad weather.
Edna's brother, Luke (Bill McKinney) appeals to Columbo to consider the case a possible homicide, based on his mistrust of Tommy.
When Hugh Caldwell (Michael McGuire) accidentally kills his wife during a fight, he calls his friend and neighbor, LAPD Deputy Commissioner Mark Halperin (Richard Kiley).
Halperin arranges the situation to make it seem that a cat burglar (Val Avery), who has recently been active in their neighborhood, is the culprit in both killings, and orders Columbo to tailor his investigation to that theory.