Every now and then Leslie Neilsen showed up as the heavy or bad guy in a few 70s shows.
He did that well in addition to comedy.
Remember him as The Swamp Fox when I was a kid. Was also in an early episode of Wagon Train.
He actually was on the airplane with my husband and I when we where in Hawaii for our Honeymoon back in 1980.
He was very nice to the people who recognized him.