'Celebrity Apprentice': George Takei, Clay Aiken, Adam Carolla Among Season 12 Contestants (Exclusive Photo)

Celebrity Apprentice Cast Promo 2012 - H 2011

Celebrity Apprentice Cast Promo 2012 - H 2011

When Donald Trump’s Celebrity Apprentice returns Feb. 12 for its fifth installment -- and 12th overall in the Apprentice franchise, it will mark its biggest season to date, upping both the number of contestants and episodes.

The sprawling cast of 18, which includes Clay Aiken, Arsenio Hall, Tia Carrere, Debbie Gibson, Adam Carolla and George Takei, will again compete for $250,000 to the charity of their choice and, Trump says, face the “biggest tasks we’ve ever had.”

“It’s hard to top the last few seasons but we think we’ve done it,” Trump tells The Hollywood Reporter of the 15-episode season. “We didn’t want to change much -- we’re not looking to reinvent the show in its 12th season.”

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“I think we have a great, very diverse cast,” he notes, citing early standouts Hall, Penn Jillette, Dee Snider, Paul Teutul Sr., Aiken, Gibson, Teresa Giudice, Lisa Lampanelli, Cheryl Tiegs and former Miss Universe Dayana Mendoza as being among the “tough and smart” surprises.

“It’s amazing the abuse they take and the kind of work they put in,” he says of the cast, which has been rumored for months but not officially confirmed until Trump made the announcement Wednesday on the Today show.

The fourth cycle of Celebrity Apprentice, which saw country singer John Rich crowned the winner, was the franchise’s lowest-rated spring finale, down 15 percent season-over-season and drawing a 2.9 rating in the key adults 18-49 demographic.

The celebrity version was first introduced as the seventh cycle of The Apprentice and came after NBC left the reality series produced and created by Mark Burnett (Survivor) off the network’s schedule. The celebrities-competing-for-charity element came as viewership for the flagship series dipped from an average of 20 million from its first season to 7 million for its sixth frame.

The freshman run of the celebrity installment that crowned Piers Morgan its winner fueled the series to a ratings uptick, with Season 7 averaging 11 million viewers.

Check out the official key art for the fifth installment of Celebrity Apprentice above and a complete cast list -- as well as the charities they’ll be playing for -- below.

Former American Idol Clay Aiken, The National Inclusion Project
Retired race car driver Michael Andretti, Racing for Cancer
Talk show host Adam Carolla, Catholic Big Brothers Big Sisters
Actor/bodybuilder Lou Ferrigno, Muscular Dystrophy Association
Actor/TV personality Arsenio Hall, Magic Johnson Foundation
Magician/TV personality Penn Jillette, Opportunity Village
Former Twisted Sister singer Dee Snider, March of Dimes/Bikers for Babies
Star Trek’s George Takei, Japanese American National Museum
American Chopper’s Paul Teutul Sr., Make-A-Wish Foundation
Actress Tia Carrere, After-School All-Stars
Singer Debbie Gibson, Children International
Real Housewives of New Jersey’s Teresa Giudice, The NephCure Foundation
Growing Up Gotti’s Victoria Gotti, Association to Benefit Children
Comedian Lisa Lampanelli, Gay Men’s Health Crisis
Miss Universe 2008 Dayana Mendoza, Latino Commission on AIDS
Singer/actress/model Aubrey O’Day, Gay, Lesbian and Straight Education Network (GLSEN)
Model/actress Cheryl Tiegs, The Farrah Fawcett Foundation
Model/actress Patricia Velasquez, Wayuu Taya Foundation

Celebrity Apprentice’s new season begins Sunday, Feb. 12 at 9 p.m. on NBC.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit