BY DAVID KRONKE >TV CRITIC

If "Knight Rider" is based on an '80s show, then "Gary Unmarried" comes to you directly from some generic sitcom world from anywhere over the past four decades. Jay Mohr stars as Gary, a likable lummox who's recently divorced from his shrewish ex-wife (Paula Marshall).

(Apparently, on the planet on which this takes place, there is no other type of ex-wife.)

When Gary grouses about having to knock on the door of his former house, his ex replies, "Of course, you don't have to knock. You can ring the bell."

To be fair, some of the other punch lines have a little more snap to them than that, but you get the sense creator/writer Ed Yeager has already run out of ideas for story lines: Tonight's episode has Gary starting a relationship with Vanessa (Jaime King), but she gets mad at him because he neglected to tell her that he's divorced with children, even though she has a big secret of her own, as well.

So plot logic and human motivations are apparently not a consideration here, and the jokes can't carry the day, either. Mohr was more engaging as the venal studio head he played in "Action."

David Kronke, (818) 713-3638 david.kronke@dailynews.com

GARY UNMARRIED

>What: Jay Mohr stars as a recently divorced guy re-entering the dating world.

>Where: CBS (Channel 2).

>When: 8:30 Wed. night

>In a nutshell: Quippy, but creaky.