<EM>Lost</EM> uncorks a shocker — or several — in May. Lost uncorks a shocker — or several — in May.

Finales! Guest stars! Crossover episodes! Mark your calendars now so you don't miss your favorite shows!

Monday, April 23
On 24 (9 pm/ET, Fox), Jack goes rogue in a desperate attempt to save Audrey from the Chinese. Wait, isn't he already rogue?

Tuesday, April 24
American Idol (8 pm/ET, Fox) lays witness to the rarely seen softer side of Simon Cowell in the two-part "Idol Gives Back" charity special. Part 2 airs tomorrow, 8 pm/ET. On ABC, boxer Oscar de la Hoya mixes it up with George Lopez (8:30 pm/ET).

Wednesday, April 25
Sun's babydaddy is revealed on Lost (10 pm/ET, ABC).

Thursday, April 26
The season's best new sitcom, 30 Rock (9 pm/ET, NBC), signs off for the summer with a visit from Thursday-night veteran Sean Hayes. Also on NBC, Earl goes back to school on My Name Is Earl (8 pm/ET). What about Randy?

Friday, April 27
Law & Order (10 pm/ET, NBC) rips from international headlines in an episode about a poisoned Russian emigré. On Numbers (10 pm/ET, CBS), Peter MacNicol returns from 24 duty, and ex-Six Feet Under nut Jeremy Sisto guest-stars as an assistant U.S. attorney.

Sunday, April 29
It's shades of Dynasty on Desperate Housewives (9 pm/ET, ABC) as Gaby and Edie square off over Carlos. Meanwhile, Ian and Mike battle over Susan, who fights with a stranger. Can't they all just get along?

Monday, April 30
No longer Vanished, Rebecca Gayheart guests on CSI: Miami (10 pm/ET, CBS) as the fiancée of a fire casualty. On Heroes (9 pm/ET, NBC), Nathan is president — five years in the future. On How I Met Your Mother (8 pm/ET, CBS), the price is right for Barney — and Bob Barker, who makes the first of his preretirement appearances.

Tuesday, May 1
Law & Order: Criminal Intent (9 pm/ET, NBC) presents the flighty case of an astronaut love triangle. Diapers optional. On Law & Order: SVU (10 pm/ET, NBC) Benson's half brother resurfaces, and Kim Delaney returns as a Jersey cop.

Wednesday, May 2
Smell the crossover as Cold Case hottie Danny Pino takes a bite out of the Big Apple on CSI: NY (10 pm/ET, CBS). One Tree Hill (9 pm/ET, CW) returns with original episodes. (Yes, it's still on.) And it's swimsuit time on America's Next Top Model (8 pm/ET, CW). Isn't it always?

Thursday, May 3
ER's Ray and Tony fight over Neela. No big deal, except they do it at Luka and Abby's wedding. It's also a big night for Grey's Anatomy (9 pm/ET, ABC) as Addison Montgomery gets a new life (and possibly a spin-off) in a special two-hour episode. On Smallville (8 pm/ET, CW), Clark flies back to the 1940s in a dream sequence. On Scrubs (9:15 pm/ET, NBC), Felicity grad Keri Russell helps plan sorority-sister Elliot's engagement "redo" in the second of a two-episode arc.

Sunday, May 6
Cold Case (9 pm/ET, CBS) closes its season by reopening a 2006 family slaying. What makes it so cold? One of the suspects is a hockey coach. On Brothers & Sisters (10 pm/ET, ABC), Sally Field's Nora and Patricia Wettig's Holly have a showdown.

Monday, May 7
On 24 (9 pm/ET, Fox), yes, someone dies tonight; no, we're not telling who. On happier notes, romance heats up between Julia Louis-Dreyfus and Blair Underwood on The New Adventures of Old Christine (8:30 pm/ET, CBS), and on How I Met Your Mother (8 pm/ET, CBS), Marshall and Lily's big day has arrived.

Tuesday, May 8
Piper Perabo checks into House (9 pm/ET, Fox) as a nutritionist who just might have the recipe to satisfy love-starved Dr. House. On Law & Order: Criminal Intent (9 pm/ET, NBC), Kristy Swanson plays a busty B-lister with a drug problem, an inheritance, a recently deceased son and a new baby. Sounds vaguely familiar. Paul Rudd goes on a mission to Veronica Mars (9 pm/ET, CW), and Bernadette Peters and Gail O'Grady are on the Boston Legal (10 pm/ET, ABC) docket.

Wednesday, May 9
A principal character dies in Jericho's first season finale (8 pm/ET, CBS), as a battle wages between the folks of Jericho and a neighboring burg. On Lost (10 pm/ET, ABC), Ben gets the flashback treatment, and John McEnroe drops by as a murder suspect on CSI: NY (10 pm/ET, CBS). Don't tell us — he has a nasty temper? And in a MySpace.com tie-in, Bones (8 pm/ET, Fox) fans can view clues to investigate a murder.

Thursday, May 10
Stanley Tucci begins a multi-episode ER arc (say that three times fast!) as the latest not-so-nice chief.

Friday, May 11
Ghost Whisperer (8 pm/ET, CBS) wraps up its season with a spooky cliff-hanger, while on Close to Home (9 pm/ET, CBS), Jonathan Silverman — star Jennifer Finnigan's real-life fiancé — finishes a three-week arc in the season ender.

Sunday, May 13
Five Survivor: Fiji contestants will be whittled down to three before the winner is chosen on tonight's three-hour finale special. On Desperate Housewives (9 pm/ET, ABC), someone says goodbye, and so does the cast of 7th Heaven (8 pm/ET, CW) in the series finale — for real this time. On Brothers & Sisters (10 pm/ET, ABC), Tommy and Julia grapple with the premature birth of their twins.

Monday, May 14
Kelsey Grammer directs the season finale of Everybody Hates Chris. Gotta love that.

Tuesday, May 15
Roy Scheider makes a rare TV appearance on Law & Order: Criminal Intent, and Rita Moreno makes a not-so-rare (but always welcome) return as Goren's schizophrenic mother. And it could be a sad night for fans of Gilmore Girls (8 pm/ET, CW), with what might be the series finale.

Wednesday, May 16
Criminal Minds (9 pm/ET, CBS) concludes its season with Keith Carradine resurfacing as Gideon's slippery arch nemesis. Tyra Banks crowns America's Next Top Model (8 pm/ET, CW), and wedding bells ring in the Bones finale (8 pm/ET, Fox). Bob Barker comes on down in The Price Is Right Million Dollar Spectacular (8 pm/ET, CBS) — the first half of a two-night going-away party. On the season finale of Medium (10 pm/ET, NBC), Neve Campbell and Jason Priestley stick a fork in a three-episode guest stint.

Thursday, May 17
Bob Barker: A Celebration of 50 Years on Television (8 pm/ET, CBS) features reminiscences and classic game-show moments. Tonight's finales include CSI (9 pm/ET, CBS), Ugly Betty (8 pm/ET, ABC), Scrubs (9 pm/ET, NBC), The Office (8 pm/ET, NBC), Smallville (8 pm/ET, CW), Supernatural (9 pm/ET, CW) and Grey's Anatomy (9 pm/ET, ABC). On the ER (10 pm/ET, NBC) finale, Goran Visnjic's Luka hops on a plane for Croatia, maybe for good. And you don't even want to know what happens to another main character.

Friday, May 18
Diane Farr returns for the Numbers finale. We know the actress was on maternity leave, but where the heck has Megan been?

Sunday, May 20
The Desperate Housewives finale features two weddings and a honeymoon extramarital affair — sounds like an average afternoon on Wisteria Lane. Other season enders include Brothers & Sisters (10 pm/ET, ABC) and Extreme Makeover: Home Edition (8 pm/ET, ABC). And Tom Selleck's back in Jesse Stone: Sea Change (8 pm/ET, CBS), his fourth TV-movie based on Robert B. Parker's best-selling mysteries.

Monday, May 21
We're going out on a limb and predicting Jack will save the world in 24's two-hour finale. Also, some lucky lady gets a proposal on The Bachelor: Officer and a Gentleman (9 pm/ET, ABC), and the first season of Heroes (9 pm/ET, NBC) ends with a frantic race to stop a hero from exploding — and destroying New York City.

Tuesday, May 22
Another big night for season enders, and they don't get any bigger than American Idol, which begins its two-night extravaganza (you'll have to tune in the following day to learn the winner). Also wrapping up the season: Dancing with the Stars (8 pm/ET, ABC), Boston Legal (10 pm/ET, ABC) and Law & Order: SVU (10 pm/ET, NBC), with guest stars Ludacris, Nancy Grace and Star Jones Reynolds. NCIS (8 pm/ET, CBS) signs off for the season with a cliff-hanger, but not before revealing a shocking secret. And taking the House slot this week is On the Lot (9 pm/ET, Fox), a moviemaking reality competition.

Wednesday, May 23
Is it too much to expect some real answers in Lost's two-hour season finale? Maybe, maybe not. Also, Chris Noth's Detective Logan finds love on Law & Order: Criminal Intent (9 pm/ET, NBC). Sadly, it's not with Sarah Jessica Parker.

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