Today on TV

Alias (7 p.m., Ch. 4): Rachel goes on her first solo mission.

Joey (7 p.m., Ch. 5): An ex-girlfriend of Joey's has an embarrassing videotape.

The O.C. (7 p.m., Ch. 13): Taylor plots to keep Seth away from Summer; Sandy works on a plan for the Newport Group.

Everybody Hates Chris (7 p.m., Ch. 24): Chris has to do the family's laundry.

Smallville (7 p.m., Ch. 30): Clark is exposed to silver kryptonite, causing him to have paranoid delusions.

Will & Grace (7:30 p.m., Ch. 5): On a trans-Atlantic flight, Will and Grace run into Grace's ex-husband, Leo (Harry Connick Jr., who's making the first of several guest appearances).

CSI (8 p.m., Ch. 2): In the first of a two-parter, a police officer is killed — but was it by friendly fire? Concludes next Thursday.

Reunion (8 p.m., Ch. 13): Tonight we find out who got murdered.

Without a Trace (9 p.m., Ch. 2): A disappearance is tied to child porn.

ER (9 p.m., Ch. 5): After what looked like an unsuccessful run for his ABC comedy "Jake in Progress," John Stamos was all set to join the cast of "ER" this season . . . but then ABC unexpectedly renewed "Jake." And the speculation was that it was a defensive move to keep the popular Stamos off "ER." But while he's not a regular, Stamos does make the first of a pair of guest appearances as a paramedic. By the way, "Jake in Progress" is slated to return to ABC's schedule in January. And, if it doesn't succeed, Stamos could always be on "ER" next season.