THE CW'S MAY SWEEP HIGHLIGHTS: VAMPIRES, WITCHES, LUCIFER, ZOD AND HUMAN GUEST STARS ABOUND

William "Billy" Baldwin Guest Stars on "Gossip Girl" on May 3, Annette O'Toole and Michael McKean Return to "Smallville" on May 7, Ryan O'Neal and Latin Pop Star Diego Boneta Guest Star on "90210," "America's Next Top Model" Visits New Zealand

April 20, 2010 (Burbank, CA) - The following are highlights of The CW's May Sweep:

Thursday, April 29

· THE VAMPIRE DIARIES - "Blood Brothers" (8:00-9:00 p.m.)

While Stefan (Paul Wesley) struggles to come to terms with his past, both he and Damon (Ian Somerhalder) reveal parts of their history to Elena (Nina Dobrev), until she finally learns the truth about how they became vampires. Pearl (guest star Kelly Hu) has an ugly confrontation with Johnathan Gilbert (guest star David Anders). Damon and Alaric (Matt Davis) try to find a mysterious invention before Johnathan does.

· SUPERNATURAL - "The Devil You Know" (9:00-10:00 p.m.)

Sam (Jared Padalecki) and Dean (Jensen Ackles) face off against the Horsemen and try to trap Lucifer himself.

Friday, April 30

· SMALLVILLE - "Sacrifice" (8:00-9:00 p.m.)

Tess (Cassidy Freeman) breaks into Watchtower, triggering an elaborate security system that Chloe (Allison Mack) installed, ultimately trapping the two women inside. Clark (Tom Welling) realizes Zod (Callum Blue) has given his soldiers super powers.

Monday, May 3

· ONE TREE HILL - "Learning to Fail" (8:00-9:00 p.m.)

Nathan (James Lafferty) and Haley (Bethany Joy Galeotti) struggle with the aftermath of her mother's death.

· GOSSIP GIRL - "It's A Dad, Dad, Dad World" (9:00-10:00 p.m.)

Will's (guest star William "Billy" Baldwin) return to the Upper East Side continues to stir up problems for Serena (Blake Lively), Lily (Kelly Rutherford) and his long-standing rival, Rufus (Matthew Settle).

Tuesday, May 4

· 90210 - "Meet The Parent" (8:00-9:00 p.m.)

Teddy (Trevor Donovan) invites a nervous Silver (Jessica Stroup) to meet his father, Spence (guest star Ryan O'Neal), for the second time and the meeting doesn't go quite as planned. Adrianna records a duet with Javier Luna (guest star/Latin recording artist Diego Boneta), a famous young pop singer, who quickly wins her over with his charm.

Wednesday, May 5

· AMERICA'S NEXT TOP MODEL - "Hobbits vs. Models" (8:00-9:00 p.m.)

The final six girls arrive in New Zealand where they learn they will participate in go-sees with six designers. This week's photo shoot finds them all modeling the same dress with a special guest -- a sheep!

ONE-HOUR SEASON FINALE With Back-to-Back Episodes

· FLY GIRLS - "The Third Wheel" (9:00-9:30 p.m.)

Jon moves to Los Angeles to work things out with Nikole. During a layover in Miami, Mandy and Louise fall for the same guy, causing a rift between the best friends.

· FLY GIRLS - "Unexpected Departures" (9:30-10:00 p.m.)

Mandy and Tasha land a coveted spot in Virgin America's national advertising campaign. Mandy confronts Louise about her deception. At 30,000 feet, Jon surprises Nikole with a big question.

Thursday, May 6

· THE VAMPIRE DIARIES - "Isobel" (8:00-9:00 p.m.)

Isobel (guest star Mia Kirshner) returns to town and stuns Alaric (Matt Davis) with her attitude and her demands that he arrange a meeting with Elena (Nina Dobrev). When mother and daughter finally meet, Isobel refuses to answer most of Elena's questions, but reveals that she will stop at nothing to find the mysterious invention Johnathan Gilbert (guest star David Anders) has been searching for.

· SUPERNATURAL - "Two Minutes to Midnight" (9:00-10:00 p.m.)

Bobby (Jim Beaver) sells his soul to help stop the Apocalypse and Dean (Jensen Ackles) goes head-to-head with Death.

Friday, May 7

· SMALLVILLE - "Hostage" (8:00-9:00 p.m.)

Much to Clark's (Tom Welling) surprise, Martha Kent (guest star Annette O'Toole) returns to Smallville with her new boyfriend, Perry White (guest star Michael McKean), in tow. Chloe (Allison Mack) helps Clark search for the Book of Rao, which they believe contains information on how to stop Zod (Callum Blue) and his army.

Tuesday, May 11

· 90210 - "Javianna" (8:00-9:00 p.m.)

Adrianna's (Jessica Lowndes) new romance with pop star Javier (guest star/Latin recording artist Diego Boneta) continues to blossom, while Navid (Michael Steger) continues to work up enough courage to tell her how he feels. Despite Spence's (guest star Ryan O'Neal) suggestion, Teddy (Trevor Donovan) refuses to end his relationship with Silver (Jessica Stroup), and the two decide to spend the night together.

Wednesday, May 12

TWO-HOUR SEASON FINALE

· AMERICA'S NEXT TOP MODEL - "Cycle 14's Top Model " (8:00-10:00 p.m.)

With the help of some surprise guests, the heat is on when the two finalists go head-to-head on the cat walk at a glam Anna Sui fashion show. As the clock ticks down, both finalists must deliver their best performance yet when they shoot their CoverGirl commercial. After evaluating both girls' work throughout the season, Tyra and the panel announce who will be America's Next Top Model.

Thursday, May 13

SEASON FINALE

· THE VAMPIRE DIARIES - "Founder's Day" (8:00-9:00 p.m.)

Founder's Day has finally arrived, and everyone is busy with last-minute preparations for floats and fireworks. Although Damon (Ian Somerhalder) and Alaric (Matt Davis) do their best to stop him, Johnathan Gilbert (guest star David Anders) sets a plan in motion that brings Founder's Day to an end amid chaos, destruction and death.

SEASON FINALE

· SUPERNATURAL - "Swan Song" (9:00-10:00 p.m.)

The showdown between good and evil is at hand. With the Apocalypse looming, Sam (Jared Padalecki) and Dean (Jensen Ackles) realize they are out of options and make heart-breaking decisions that will change their lives forever. A beloved character faces death.

Friday, May 14

SEASON FINALE

· SMALLVILLE - "Salvation" (8:00-9:00 p.m.) When Zod (Callum Blue) and the Kandorians launch their brutal attack on Earth, Chloe (Alison Mack) calls in some old friends to join the fight against the aliens. Clark (Tom Welling) and Zod face off in an epic battle for the control of Earth.

Monday, May 17

SEASON FINALE

· ONE TREE HILL -

"Almost Everything I Wish I'd Said the Last Time I Saw You..." (8:00-9:00 p.m.)

Haley (Bethany Joy Galeotti) tries to overcome her depression by joining Nathan (James Lafferty), Jamie (Jackson Brundage) and the rest of the Tree Hill gang on a trip to Utah for the premiere of Julian's (Austin Nichols) film.

SEASON FINALE

· GOSSIP GIRL - "Last Tango, Then Paris" (9:00-10:00 p.m.)

Blair (Leighton Meester) must decide whether to meet Chuck (Ed Westwick) at the top of the Empire State Building or risk losing their future together. A Gossip Girl gossip bomb involving Dan (Penn Badgley) causes major problems for Serena (Blake Lively) and Nate (Chace Crawford). Georgina Sparks (guest star Michelle Trachtenberg) returns to the Upper East Side...and she has an agenda.

Tuesday, May 18

SEASON FINALE

· 90210 - "Confessions" (8:00-9:00 p.m.)

Teddy (Trevor Donovan) discovers that Spence (guest star Ryan O'Neal) tried to bribe Silver (Jessica Stroup) and takes it upon himself to seek revenge in a most confrontational way. Annie (Shenae Grimes) and Liam (Matt Lanter) test out the waters with his new boat, where they share their darkest secrets. Little do they know that someone is nearby and decides to share an explosive flame of gasoline with Liam's boat.