TONIGHT'S MUST-SEE

"Live Earth: The Concerts for a Climate in Crisis," 7 p.m., NBC. Also, 4 a.m. to 9:30 p.m., Bravo; 1 to 8 p.m., CNBC. Here is a massive event, with nine concerts on seven continents, including eco-messages. NBC will have lots of performers to choose from. Plans call for Kelly Clarkson, John Mayer, The Police, Madonna, Faith Hill, Kanye West, Bon Jovi, Shakira, Sheryl Crow, Black Eyed Peas, Melissa Etheridge, Enrique Iglesias, Fall Out Boy, Duran Duran, Jack Johnson and more.

OF NOTE

"The Devil Wears Prada" (2006), 5 p.m., HBO. Director David Frankel found the perfect blend of comedy, glamour and subtle characterizations. Anne Hathaway is excellent as the wide-eyed newcomer and Meryl Streep is perfect as her steel-souled boss.

"Avenging Angel," 6 p.m., Hallmark. Kevin Sorbo may be perfect for a classic cowboy role. Sorbo is best-known as TV's Hercules; a sampling here shows him capturing all the nuances of a strong-and-silent bounty hunter in the Old West, harboring pain and revenge.

"Assume the Position 201 With Mr. Wuhl," 7 p.m., HBO. Here's the second special with Wuhl in a classroom, relating odd parts of U.S. history. There are hilarious moments plus a message: Don't worry; we've seen worse. Consider presidents and flooding: Wuhl says Calvin Coolidge took a three-month vacation while several states were flooded. He was fishing — in a lake that was secretly restocked each night.

"Harry Potter and the Chamber of Secrets" (2002), 7 p.m., ABC Family. The second Potter film has students turning into stone. It also has a dandy role for Kenneth Branagh, as a teacher whose ego exceeds his talent.

"Monsters, Inc." (2001), 7 p.m., ABC. Here's one of the computer-animated hits from Pixar. A little girl accidentally reaches Monstropolous.

"Cold Case," 7 p.m., CBS. Back in 1973, this rerun says, a rising female tennis player beat a male in a heavily publicized match; she was then found dead in her college dorm. Now fresh evidence revives the case.

"Four Weddings and a Funeral" (1994), 8 p.m., E. Hugh Grant stars, backed by other talented English people, including Rowan Atkinson.

"Saturday Night Live," 10:30 p.m., NBC. Forest Whitaker hosts, with Keith Urban as the musical guest.