Fun for them to get Johnny Cash and not just have him be a murderer, but be a completely unrepentant one. Bro said "Take my wife.... please!" and when no one did he just crashed a plane into the side of a mountain. It being Johnny Cash does kind of immediately engender some sympathy towards him, so that when he lands a little far from the crash and sees a car driving towards it, there's a tension to it as we watch him try and hide the parachute and hobble his way over so he can make his story work. Love the scene where Columbo first arrives at the crash and he interrupts the interview, but then the questions he's asking makes the guy doing the aviation investigation keep breaking off from the interview to go talk to him instead. Those patented little questions that get peoples' mind going, like "why was his seat belt unbuckled" and "why aren't there ashes in the navigation kit." It's perhaps not the greatest investigation of them all but there's an undeniable delight to Falk and Cash together here, Cash's deep, booming voice at once comforting and threating - he's a Very Large Man in comparison to Columbo, and then when his brother-in-law comes over and just straight-up decks him at some point too you can see how he'd be good in a rumble. A little weird for fictional Cash to be embroiled in a blackmail scenario about committing statutory rape, when it looks like real-life Cash might have done the same thing? He certainly met his one of his wives while she was underage. Very fun though and certainly one of the more daring murders we've seen so far. The audacity! Crashing a plane? And then days later going "oh yeah the thing my wife was working on, the tabernacle? Cancel that, I'm just gonna be out here with my young hotties and oodles of dough."