Nathan Fillion

CASTLE (ABC)

Airs: Mondays at 10 p.m.

Cast: Nathan Fillion, Stana Katic

Nathan Fillion, as millionaire playboy mystery author Richard Castle, and Stana Katic, as edgy N.Y. detective Kate Beckett, are midseason TV’s most charming odd couple. Beckett’s hard-driving nature and finely honed detective technique mesh nicely with Castle’s brilliant instinct for sussing out means, motive and opportunity—he did it for his fictional characters, and he easily transfers the skill set to actual crimes. As Nathan Fillion tells us, "[Castle’s] having a blast, but he’s not driven to find justice—he just wants the beginning of the story. The end is murder, he wants the beginning. He’s fascinated by story. That’s what drives him."

Verdict: Nathan Fillion is back on TV playing a lovable scamp—how could you possibly say no?!