Paris & Nicole will take RV cross-country

Paris and Nicole are trading in their limo for a Winnebago.

Fox has greenlit production on a second cycle of “The Simple Life,” the unscripted rich-girls-out-of-water hit from Bunim-Murray Prods. and 20th Century Fox TV. Paris Hilton and Nicole Richie have both signed on for “Simple Life 2,” which will begin production next month and likely bow in time for the May sweeps.

Jonathan Murray will exec produce.

Rather than reunite with season one’s Leding family or settle down in a different small town, Hilton and Richie will go mobile for season two.

“It’ll be a cross-country road trip where they travel from town to town and go from family to family,” said Fox reality supremo Mike Darnell. “The show can be a different experience in every episode.”

Darnell said the show will be a cross between the National Lampoon “Vacation” franchise and Bunim-Murray’s own long-running unscripted MTV hit “Road Rules.”

There’s no firm decision yet on whether Hilton and Richie will actually travel by RV, though such a scenario certainly would provide plenty of fodder for the show.

While Hilton and Richie have jetted around the globe, Darnell noted the two so-called celebutantes haven’t visited huge chunks of the U.S.

“It’ll be interesting to see the country through their eyes,” he said. “Maybe Paris will visit a Wal-Mart. I’m kind of hoping they stop at a Hilton.”

Hilton and Richie are expected to spend a little less than a month on the road, giving WMA-repped Bunim-Murray and 20th material for eight to 10 episodes (though there’s always the chance of a “lost” episode or two).

The first “Simple Life” was an instant ratings hit, helping give Fox some much-needed momentum after the net’s traditionally troubled November sweeps. “American Idol” and “My Big Fat Obnoxious Fiance” have put Fox back in the ratings game, and the addition of “SL2″ to the net’s schedule promises to make the already tight race for first place among adults 18-49 even more interesting.

Casting for “SL2″ will begin this weekend, with producers scheduled to hold auditions in Grand Canyon Village, Ariz.; Brooksville, Fla.; and Lafayette, La.

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