Byline: Maureen Ryan

As viewers saw on the Sept. 30 Season 2 premiere of "Dexter" (Sundays, 9 p.m. EDT on Showtime), Dexter Morgan is a changed man.

This terrific Showtime series is giving us a much more tentative serial killer this year. Before you exclaim, "Serial killer! Why would I watch a show about someone like that?" consider this: Dexter is one of the more compelling men on TV.

This clever series, which sprang from a series of mystery novels by Jeffrey Lindsay, turns the notion of "innocence" on its head. The wide-eyed Dexter (Michael C. Hall) doesn't consider himself human, but he's often as mystified and sweetly clueless as the most naive ingenue. He's ...