By Tom Gliatto Cynthia Wang
March 19, 2007 12:00 PM

24 (FOX, March 12, 9 p.m. ET) The day has reached 6 p.m., and Rick Schroder turns up at CTU as a guy named Mike Doyle. Try not to get in the way, Mike.

Grey’s Anatomy (ABC, March 15, 9 p.m. ET) Oscar nominee Shohreh Aghdashloo (a star on CBS’s short-lived Smith) turns up as a patient with the moniker Helen Crawford.

Without a Trace (CBS, March 11, 10 p.m. ET) Series star Anthony LaPaglia conceived and cowrote this episode about a missing Senator and her not terribly helpful father.

The New Adventures of Old Christine (CBS, March 12, 8 p.m. ET) Julia Louis-Dreyfus’s very funny sitcom about a single mom returns with back-to-back episodes.

Identity (NBC, March 16, 9 p.m. ET) A comeback for the quiz show with one contestant, 12 strangers and a $500,000 prize. It sounds just like my family reunion!