I've always enjoyed "UNDERCOVER", even though it's not at all in the Columbo formula. The best part, to me, was the interaction between Columbo and Sgt. Brown (Harrison Page). Also giving a strong performance is the usually "meh" Shera Danese. Burt Young's appearance is an added bonus. Some light moments and some good detective work type of scenes. I thought Tyne Daly's performance was actually quite good. The "I don't like memories" conversation with Columbo is somewhat poignant. I know some will disagree with Columbo getting pistol-whipped and actually pulling a gun on someone, but it feels like the right thing for him to do as an undercover cop messing with a tough guy.
It's literally not a COLUMBO episode.
Falk bought the story not knowing it wasn't suitable for adaptation .
He only filmed it because he spent the money. The character is named " Columbo" but it's not our COLUMBO.