Alex O'Loughlin, Carol Burnett

CBS's Hawaii Five-0 serves up a treat on its Nov. 22 Thanksgiving episode when Steve McGarrett's loopy Aunt Deb — played by comedy legend Carol Burnett — lands on the island.

"Deb at one time had been a singer, but she gave up any hopes of a career to raise [her niece] Mary Ann. So the gang takes her to a restaurant and tricks her into getting up and singing a song," says Burnett, a die-hard Five-0 fan who recorded Annie Get Your Gun's "I've Got the Sun in the Morning and the Moon at Night" in L.A. before flying to Oahu to shoot her scenes.

But the reunion turns bittersweet when Deb gets arrested and drops a bombshell on her nephew (Alex O'Loughlin) and niece (Taryn Manning). "She planned to tell everybody her secret," Burnett adds, "but it comes out a little too soon."

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