TiVo Guide Week of March 30, 2009 *spoiler alert*

“Chuck” When Chuck and Sarah's complex relationship is exposed, a cold female agent (Tricia Helfer) is assigned to evaluate Sarah's performance, putting her job in jeopardy. Elsewhere, Morgan and "Jeffster" set out to attend Awesome's bachelor party. Monday at 8 on NBC.

“Greek” Casey returns from her summer internship with secret plans to move out of her sorority house. Elsewhere, Calvin's high-school buddy Andy (Jesse McCartney) begins his freshman year and gets courted by both Calvin and Rusty's fraternities; and Rusty adjusts to living at the Kappa Tau house. Monday at 8 on ABC Family.

“Osbournes: Reloaded” Ozzy, Sharon, Jack and Kelly star in a variety show that features them performing comedy, interacting with the audience and appearing in recurring segments outside the studio. In the opener, a blindfolded audience member is asked to kiss a stranger, and Kelly and Ozzy work at a fast-food drive-thru in a segment called "Osbourne in the USA." Tuesday at 9:20 on Fox.

“Real Housewives of New York City” In one corner: Kelly. In the other: Bethenny. The two housewives square off in a diva duel during a downtown bar meeting. In other unfolding dramas, all six wives assemble at a magazine party, where Kelly reflects on her fight with Bethenny. And there's back-and-forth tension over an upcoming tennis match. Tuesday at 10 on Bravo.

“Real World” The roommates say good-bye to Brooklyn and each other as the 21st season comes to a close. Wednesday at 10 on MTV.

“Life on Mars” In the series finale, a mysterious caller offers Sam a chance to return to 2008, but a confusing set of circumstances makes him wonder whether he even wants to do it. Wednesday at 10:02 on ABC.

“CSI: Crime Scene Investigation” One of Ray's former students is murdered, and the investigation plunges the team into the mysterious world of Mexican wrestling. William Friedkin directed the episode. Thursday at 9 on CBS.

“ER” In the series finale, old friends from County show up to support Carter as he opens a new medical facility for Chicago's less fortunate. Meanwhile, Gates treats a teen suffering from alcohol poisoning as a result of a drinking game; and an intern turns to Carter for help with a woman who has gone into labor with twins. Alexis Bledel and Ernest Borgnine guest star. Thursday at 9 on NBC.

“Yo Gabba Gabba!” Jack Black gets lost in Gabbaland. After meeting the Gabba gang, he becomes friends with them and they refuel his minibike. But before returning home, he sings and does a dance called the Disco Roll. Jack McBrayer and Paul Scheer also make appearances. Friday at 1:30 on Nickelodeon.

“Party Down” The caterers work a senior singles mixer organized by a spicy host; Constance and an old flame have an uncomfortable reunion; Casey is in the market for some sound relationship advice. Friday at 10:30 on Starz.

“Love Takes Wing” A young doctor (Sarah Jones) moves to a town where a strange illness has stricken several residents, particularly those in the local orphanage. Despite their peril, the townspeople resist her efforts to help because she's a woman, so the doctor must find a way to save the town before it's too late. Haylie Duff, Cloris Leachman, Patrick Duffy. Directed by Lou Diamond Phillips, who also stars. Based on the novel by Janette Oke. Saturday at 9 on Hallmark.

“Nora Roberts’ High Noon” As a hostage negotiator and mother (Emilie de Ravin) begins a romance with a charming bar owner (Ivan Sergei), she becomes the primary target of a psychopathic serial killer. Cybill Shepherd also stars. Saturday at 9 on Lifetime.

“Food Network Challenge” Part 1 of 4. Six pastry chefs begin vying for the title of "Best Cake Artist in America" and a $50,000 grand prize. In the first of four competitions, each has eight hours to tell a personal story in cake. At the end of the day, one hopeful will be eliminated. Sunday at 8 on Food.

“In Treatment” In the second-season premiere, Paul, recently divorced and living in Brooklyn, reconnects with a lawyer and former patient, Mia (Hope Davis), whose firm helps him with a legal problem. Sunday at 9 on HBO.