Sharon Gless Sharon Gless

Guess Neil Young was right: It is better to burn out than to fade away. "We're going out with a bang," Sharon Gless says of Thursday's Burn Notice's series finale. "The last scene will matter immensely. It's gonna be shocking. People will be stunned. But there's a sweetness at the end."

Gless would expect nothing less after her seven-year run as spy mom Madeline Westen on USA's top-rated drama. "It's been quite a ride," she says. "Madeline has grown tremendously — she started out as this manipulative, chain-smoking hypochondriac, and then they started to bring her into the work." Early on, creator Matt Nix gave Gless a key to her character. "He said, 'Michael [Jeffrey Donovan] got all his moxie and smarts from this woman,'" Gless recalls. "That's what I ran with for seven years."

Over that time, Gless formed a familial bond with Donovan. "His [real-life] mama is gone, and off camera, he calls me mama," she beams. "When I first heard the show was ending, I was at a bowling alley with Jeffrey, and I turned to him and said, 'I'm gonna miss you.' and I started to cry!"

As for her post-Burn plans, "I'm going to a fat farm!" she says with a laugh. "I put on a few pounds after I quit smoking, so I want to take off some weight and get healthy." But she's not shedding her career. "I've been very, very blessed," says the Emmy-winning veteran of such shows as Marcus Welby, M.D.; Cagney & Lacey; Queer as Folk and Nip/Tuck. "For 41 years, I've been doing this. I ain't quitting now."

Burn Notice airs its series finale Thursday, Sept. 12 at 9/8c on USA.

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