Now here's a reality show where the participants not only live together in the same house — they climb its walls, too.

Welcome to "Cold Turkey," (search) the first reality series to ask the question: What would happen if you forced 10 heavy smokers, all in the throes of nicotine withdrawal (search), to reside under the same roof for 24 days?

The answer, according to executive producer Stu Krasnow, is: You get a houseful of very irritable people.

"When you do these shows, you really want the cast to pretty much be happy by the end of the day," says Krasnow, the producer of "Average Joe" and other shows.

However, he says, "This was not a show about people going to sleep and being fine at the end of the day. And I'll tell you, it took its toll on the staff, on the crew, on myself — it was very difficult."

The one-hour "Cold Turkey" starts a 10-episode run on Sunday, Oct. 3, at 10 p.m. on Pax. Hosted by A.J. Benza (formerly of E!'s "Mysteries and Scandals" series), "Cold Turkey" was filmed last May and June in a rented mansion in Calabasas, Calif.

For the show, 10 participants were lured to California to take part in a reality show. None of them, however, knew the show would address their heavy smoking habits. Each of them thought they were being invited to participate in a different show.

For example, one was told he would get to drive in a NASCAR race (search). Another thought he would be training as an astronaut. And a female participant was convinced she would be competing to become queen of her own private island.

Instead, they are soon informed that they have been recruited to quit smoking for the benefit of family members who secretly contacted the show and signed them up.

For Pax, "Cold Turkey" is a key element in a revamped lineup to be unveiled next month that has been assembled under the direction of NBC, 36-percent owner of Pax. Although their relationship has been contentious, NBC has been providing consulting services to Pax since last January.

One result is "Cold Turkey," which Krasnow feels is a perfect fit for Pax, a network known for its inspirational programming.

"['Cold Turkey']," he says, "is a reality show with a social message."