You know - a guy who has a well-defined image, who doesn't take himself too seriously, and who - unlike Shatner - did all of his own stunts.
And if this Columbo episode proves anything, it's that Robert Conrad could act if given the right script.
Think of it this way - An Exercise in Fatality was produced five years after The Wild Wild West was canceled....not by low ratings, mind you, but by the then-prevalent movement to reduce violence on television. It would have been easy for Conrad to descend into his eventual image of a tough guy who knew no limits. We've all seen the commercial:
But here's Conrad taking a well-deserved risk: he plays Milo Janus, a fitness guru who has been engaging in what my father might refer to as "creative bookkeeping". When one of his franchise owners starts digging, well....let's just say the phrase "killer workout" will apply.
And one of the great things that I love about this Columbo - perhaps more than any other - is that there is a palpable sense of threat against the detective. Sure, Falk does his best to diffuse Conrad with humor (trust me, nothing says "comedy gold" like Columbo in a sweatsuit), but the script takes great pains to not only make Janus a very clever adversary....but also quite a formidable one as well.
(Unlike Ross Martin, who seems more annoyed than malevolent in Suitable for Framing, or even Shatner's turn in Fade Into Murder which felt too self-referential....but those are posts for another time)
To be honest, I felt the ending reveal was....well, a bit weak. (Given that Peter S. Fischer - who later co-created Murder She Wrote - and Larry Cohen were involved, I'm quite surprised). However, when watching it again, I realized that Conrad had such a presence throughout An Exercise in Fatality that on some level, I was hoping he would get away with murder.
(Also, extra bonus - a brief walk-on by the actor who played Ham in Doc Savage: The Man of Bronze)
This is one of the better Columbo episodes. Worth checking out.