There lies for me the only problem with this entry: it's too darn long. Leave out the preposterous chopper chase scene (replace it with any other remotely plausible twist you may think of), and one or two of the "funny" bits, and there you have the series' masterpiece.
I will add to the already mentioned enormous qualities and production values of this entry (for a TV show) the cinematography, making nice use of light and shade in several scenes (watch the window transoms throwing "prison bar" shades on Halperin's - the villain - face! ...and another shot also using a single vertical bar shade on his head). And also the camera-work, especially when Columbo gets to his final point of accusing Halperin, when the camera slowly drops down from Columbo to the former's profile in close-up, just as he takes in Columbo's doom - word for fraction of a second: absolutely priceless!
I will add to the already mentioned enormous qualities and production values of this entry (for a TV show) the cinematography, making nice use of light and shade in several scenes (watch the window transoms throwing "prison bar" shades on Halperin's - the villain - face! ...and another shot also using a single vertical bar shade on his head). And also the camera-work, especially when Columbo gets to his final point of accusing Halperin, when the camera slowly drops down from Columbo to the former's profile in close-up, just as he takes in Columbo's doom - word for fraction of a second: absolutely priceless!