Constantine Maroulis and Wayne Brady, Don't Forget the Lyrics

Don't Forget the Lyrics!
9 pm/ET Fox
Fans of American Idol will want to make sure they tune in to tonight's competition, as it features Constantine Maroulis, the rock vocalist who finished sixth on the talent show's fourth season. Maroulis will try to win money for Broadway Cares/Equity Fights AIDS, the not-for-profit AIDS fund-raising and grant-making organization. — Joe Friedrich

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Stargate Atlantis
9 pm/ET Sci Fi
It's not easy being a member of the Atlantis expedition. You fight the Wraith (who would happily turn you into dinner), you battle technology-gone-bad called Replicators, and what thanks do you get for saving countless lives in the process? If you happen to be on Sheppard's team tonight, you get put on trial for crimes against humanity. When an interplanetary council tires of the team's shenanigans in the Pegasus Galaxy, Woolsey must find his inner Perry Mason to win an acquittal for the heroes. — Michael Chant

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South of Nowhere
8:30 pm/ET THE N
Kyla and Ashley's sisterly bond has had its share of ups and downs, and tonight Kyla takes steps to make that bond stronger. As she deals with the aftermath of being embarrassed on national television, Kyla decides to try to redeem herself by being honest with Ashley. Will Ashley be receptive to a humbled Kayla, or will she turn her back on her? — Jennifer Sankowski

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NUMB3RS
10 pm/ET CBS
Last week, Don discovered that Charlie now works for the LAPD as a consultant. Don also told Agent McGowan (the steely Keith Carradine) that he will leave the Bureau if Charlie isn't reissued a security clearance. That probably wouldn't upset McGowan too much since he seems to loathe Don, which will make his decision all the more interesting when he hands it down tonight. Meanwhile, Don assists a veteran FBI agent (Henry Winkler) track an elusive con man who has evaded capture for years. — Tim Holland

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Starter Wife
10 pm/ET USA
After spending last week's episode in hiding, Molly finds that her fortunes take a different — and somewhat suspicious — turn. The scheming Eve sets up a meeting between Molly and her agent husband, who is interested in Molly's work and insight into Hollywood. But is it too good to be true? Elsewhere, Joan pursues her interest in David Shea, despite the objections of her friends. — Brie Hearn

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