TONIGHT'S MUST-SEE

"Free Ride" debut, 8:30 p.m., Fox. After graduating from college, Nate (Josh Dean) hasn't decided what to do with his life. He returns to Missouri to enjoy some free living at his parents' house. His parents (Allan Havey and Loretta Fox) aren't pleased about this. They've turned his room into a workout space and grudgingly offer him the garage. The beautiful Amber (Erin Cahill) still lives in town. So does Mark Dove (Dave Sheridan), a party kind of guy who hasn't changed much since high school. The result is offbeat and funny, which probably shouldn't surprise us. Rob Roy Thomas, who created the witty "Significant Others," created this show. That show spent two years on Bravo using improvised dialogue. Thomas uses the same technique here: He outlines the situation, but not the dialogue. A clever cast does the rest and brings some new fun to the old world of situation comedy.

OF NOTE

"American Idol," 7 p.m., Fox. After whipping the "Winter Olympics" in the ratings, "American Idol" takes on "Lost" (but more on that later). Tonight, the 10 remaining men sing.

"Freddie," 7:30 p.m., ABC. Freddie's pal Chris has lots of restaurant ideas — none of them good.

"Windsor Castle: A Royal Year" conclusion, 8 p.m., PBS. For more than 50 years, Prince Philip has officially been the ranger for the Windsor Castle and its massive grounds. His domain is a popular park for everyone from joggers to dog-walkers. He has also tried other notions, such as creating a fresh-food market and a polo field. This hour offers brief glimpses of a polo match that includes Prince Harry and the wedding of Prince Charles. It also offers many looks at Philip, who comes across as a pleasant chap.

"Lost," 8 p.m., ABC. In a new episode, Claire's baby takes ill so she heads back to the site of her kidnapping in hopes of finding a cure for his illness. Kate and Rousseau tag along. Meanwhile, Jack and Locke still haven't told anyone they have a mysterious prisoner.

"Barbara Walters Academy Award Special," 9 p.m., ABC. Walters' annual interview special used to run on Oscar night. This year it's running four days early. George Clooney and other celebrities sit down for a chat.