Conan O'Brien Shows Off His Halloween Costume on video.

Nick Cannon and Mariah Carey attend a Halloween celebration at M2 Ultra Lounge Oct. 31, 2009 in New York City.

"LIVE! with Regis and Kelly's" 2009 Halloween special featured the two show hosts donning 20 costumes, the most in the history of the annual fright fest. They dressed up as Jon and Kate Gosselin, Lady Gaga and Susan Boyle, the Real Housewives of New Jersey, and many, many more. With co-host Regis Philbin sporting a werewolf get-up, center, with claws, co-host Kelly Ripa, in red, fronted a cast of dancers in a tribute to Michael Jackson's iconic "Thriller" video.

Regis Philbin and Kelly Ripa outfit themselves as "Jon and Kate Plus 8" stars Kate and Jon Gosselin on "LIVE! with Regis and Kelly's" 2009 Halloween special, "LIVE's Reality Bites Halloween Spectacular."

"Dancing with the Stars" judge Carrie Ann Inaba joined "Len Goodman" (Regis Philbin) and "Bruno Tonioli" (Kelly Ripa) to judge "LIVE! with Regis and Kelly's" annual costume contest on the 2009 Halloween special, "LIVE's Reality Bites Halloween Spectacular."

It was a very ghoulish time for the cast of "The View" during their annual Halloween-themed show Oct. 30, 2009. The cast debuted their costumes, which included Whoopi Goldberg as She Who Will Not Be Named, Joy Behar as Vampira, Sherri as the Queen of the Damned, Elisabeth Hasselbeck as Countess Chocula and Barbara Walters as the goth incarnation of "True Blood's Fangtasia."

Whoopi Goldberg, dressed as She Who Will Not Be Named and Elisabeth Hasselbeck as Countess Chocula, interview Medusa for "The View's" Halloween show. How fitting.

Barbara Walters followed the vampire trend that has been all the rage, dressing as the goth incarnation of "True Blood's" Fangtasia.

He came to suck your blood! Fox News host Bill O'Reilly dressed as Count Dracula for "The View's" Halloween show Oct. 30, 2009.

Mario Cantone

Elisabeth Hasselbeck

Joy Behar

Sherri Shepherd

Whoopi Goldberg

Whoopi Goldberg