An open-and-shut case? It's never that easy on "The Closer," let alone any of today's brain-baffling crime dramas.

Thankfully, Kyra Sedgwick makes it OK to be befuddled. Her standout portrayal of Deputy Police Chief Brenda Johnson is the triumphant Exhibit A of TNT's hit whodunit, which returns for a second season tonight.

As a kid in presumably simpler times, Sedgwick says she watched "Columbo," "Baretta" and "The Nightstalker" with scant idea of where the story would lead.

"I watched them for the characters," she says in a telephone interview. "I didn't watch them for the plot, because I could never follow the plot. Let me tell you, it's the hardest part of my job now, too. The easiest part is the character part."

Sedgwick, married to actor Kevin Bacon, is a wonder as "The Closer's" Southern-fried, sugar-loving boss lady. Transported from Atlanta to the LAPD, Brenda busts chops when required. But she's also insecure, sometimes downright neurotic and often home alone when her first love calls.

"Hi, Momma," she'll say in what's become a tag line. As has "All right then," even though Sedgwick is surprised to hear this.

"You know what, I haven't noticed that one," she says. "But now that you've mentioned it, maybe it is."

Still a diehard New Yorker, Sedgwick says she's learning to cope with spending months on end in Los Angeles, where "The Closer" is filmed.

"When I think about being here for half the year, it's a scary thought," she says. "But it's beautiful, and it's warm. You can get out to the mountains and to the ocean, so I have adjusted."

For the first time, she's also wedded to the same character for what looks to be a lengthy run. Might that be a problem for an actress who values her versatility?

"I'm not having any trouble with that yet," Sedgwick says. "They keep putting me in situations where I have to come up with something different. I'm able to keep unraveling the mystery of Brenda, so I don't feel stuck in any way."

She pauses and adds, "But now you've got me worried."

Didn't mean to do that. Long live Brenda Johnson.