TONIGHT'S MUST-SEE

"ER," 9 p.m., NBC. John Leguizamo steps in tonight, possibly giving a much-needed boost to this meandering show. "I play kind of a genius doctor — really bright and kind of self-serving," Leguizamo says. "I'm bringing in a lot of gadgets." The hard-working doctors at County General might not appreciate that. Leguizamo is the new attending physician but arrives disguised as a patient. That's hard on Pratt (Mekhi Phifer), who has other problems. His bad-news dad (Danny Glover) is back, claiming to be reformed. Meanwhile, Kovac is bonding with the formerly comatose patient he met last week and a breast cancer patient convinces Abby to get her first mammogram. Leguizamo has been brilliant in "Arabian Nights" (as multiple genies), "Ice Age" (as the voice of Sid) and two superb Baz Luhrmann films, "Romeo and Juliet" and "Moulin Rouge!" Leguizamo, who also is starring in the "Ice Age" sequel, has signed on for at least 12 episodes. This may be just the kick in the pants that "ER" needs.

OF NOTE

"Jerry Maguire" (1996), 5 and 8 p.m., TNT. Cameron Crowe wrote and directed a beautifully detailed film about a slick sports agent who makes the revolutionary decision to be honest. Tom Cruise is perfect in the lead but the real joy is in the supporting cast. Renee Zellweger and Jonathan Lipnicki are wonderful as an aide and her son. There's also fine work from Cuba Gooding Jr. (winning an Oscar), Jay Mohr, Jerry O'Connell, Kelly Preston and more.

"Joey," 7 p.m., NBC. Joey is so struck by a girl that he wants to take the same class she does — even though that's English as a second language. Meanwhile, his sister is supposed to help his agent come up with a new client.

"Will and Grace," 7:30 p.m., NBC. Jack suggests Karen would be better off with Stanley — the husband she thought was dead — than with Malcolm (Alec Baldwin). Meanwhile, Will befriends Clyde. Grace, however, sees Clyde as the lonely old gay man Will might become.

"The Apprentice," 8 p.m., NBC. The teams are designing floats to promote a science-fiction movie.

"CSI: Crime Scene Investigation," 8 p.m., CBS. Officials assume some members of a small-town family were killed. Nick thinks some of them might still be alive.

"Without a Trace," 9 p.m., CBS. After intense interrogation, a professor signed a murder confession. Seven years later, Jack and Vivian have doubts.

TONIGHT ON K5 NEWS

Tonight, K5 News at Nine takes you to Las Vegas for an insider's look at Hawai'i's favorite vacation destination. It's tonight's Vegas Minute. Also on K5, the Rainbow Wahine take on Utah State live from the Stan Sheriff Center at 7 p.m.