TONIGHT'S MUST-SEE

"Mean Girls" (2004), 7 and 9 p.m., ABC Family. As the writers' strike grows, we find ourselves perilously close to having a Thursday without Tina Fey's sharp-witted comedy. NBC now alternates its four Thursday comedies into two spots. Tonight, there are reruns of "My Name is Earl" (the warden wants Earl to settle a gang rivalry) and "The Office"; on the shelf are "Scrubs" and Fey's "30 Rock." Fortunately, ABC Family has a temporary fix. "Mean Girls" is an above-average comedy, with Fey as the writer and a co-star. Lindsay Lohan — a solid and skilled actress, no matter what other problems she has — plays the new kid at a high school, tugged between the in crowd and the geeks. The cast includes Rachel McAdams, Lacey Chabert and several "Saturday Night Live" people — Amy Poehler, Ana Gasteyer and Tim Meadows.

"Without a Trace," 7 and 9 p.m., CBS. Filling a temporary spot until "Survivor" returns, "Trace" gets a rerun and then a new episode. In the first, a divorce judge has disappeared. There are plenty of possible explanations. In the second, a worker at a veterans hospital is missing. Early suspicions involve an anti-war group.

OF NOTE

"Ugly Betty," 7 p.m., ABC. Claire goes on trial, accused of killing Fey Summers. Meanwhile, a perfume created by Fey has a strange effect on Betty and Henry.

"Are You Smarter Than a 5th Grader?" 7:30 p.m., Fox. Is a beauty queen smarter than fifth-graders? Tonight, Lauren Nelson, who is Miss America, plays for charity.

"Casablanca" (1942), 3 p.m., Turner Classic Movies. On a weak night for new TV, you might want to sink back into a classic. Humphrey Bogart and Ingrid Bergman star in this bittersweet film, set at a nightclub where people, displaced by the start of a world war, find their lives in limbo.

"Under the Tuscan Sun" (2003), 6 and 8:30 p.m., WE. Diane Lane, now starring in the big-screen "Untraceable," did her usual first-rate job in this gracefully paced drama. She plays a frantic American who suddenly changes her pace and her life, buying an old villa.

"CSI: Crime Scene Investigation," 8 p.m., CBS. In his rerun. everyone in a family was killed except for a girl, who some believe is possessed by the devil.

"The Celebrity Apprentice," 8 p.m., NBC. Each team is given a trailer and a graphics artist and told to create a mobile printing station. Problems range from a demanding team leader to the ultimate crisis — coffee spilled on a computer.

"Grey's Anatomy," 8 p.m., ABC. Here's a rerun of an episode that was — by this show's high standards — only so-so. Patients include someone from a skydiving accident and two women in a frantic competition for a wedding gown. Meanwhile, Izzie and Cristina compete for surgical assignments, and the chief pressures his colleagues into a "gentleman's evening."

"Big Shots," 9:01 p.m., ABC. This show still has a couple of new episodes to air. Tonight, James and Katie (Michael Vartan and Nia Long) disagree about revealing their relationship. Duncan and Terrence (Dylan McDermott and Paul Blackthorne) disagree about a public-relations problem; Brody (Christopher Titus) has doubts about helping a base ball player.

"ER," 9:01 p.m., NBC. Parminder Nagra first drew raves in "Bend It Like Beckham," in which she played someone fighting obstacles to play soccer. Now her "ER" character (Neela) joins a hockey team. In another story, Julia (Reiko Aylesworth) works with a prison doctor who feels guilt about giving lethal injections.