Season synopsis
Contains spoilers for this season and earlier seasons.
The third season sends Lieutenant Columbo from a cosmetics laboratory to a family winery, a Senate campaign and a research company. Beauty Mark’s owner Viveca Scott kills a chemist over a stolen wrinkle cream; wine expert Adrian Carsini murders his younger half-brother after he plans to sell their winery. Candidate Nelson Hayward exploits the assassination threats he invented for publicity to kill campaign manager Harry Stone, while researcher Bart Keppel kills an executive and tries to make the victim’s wife look responsible. Publisher Riley Greenleaf goes further, hiring a gunman to kill the author who intends to leave his firm.
Other cases involve a scientist who kills a professor to hide his son’s plagiarism, and gospel singer Tommy Brown, whose plane crash kills his evangelist wife after she threatens to expose him. In the finale, deputy commissioner Mark Halperin helps neighbor Hugh Caldwell disguise Caldwell’s killing of his wife as a burglary, then expects Caldwell to return the favor after Halperin kills his own wife. Columbo questions Halperin’s advance knowledge of the first death and makes Halperin believe a jewel thief’s address is real. Halperin’s attempt to plant stolen jewels there reveals that the apartment is a trap Columbo prepared, tying the senior officer to the cover-up.