According to Variety, it's Jack Bauer's most unusual assignment yet: Administer the takeover of five major-market radio stations for 24 hours. (Insert "24's" by-now familiar "clink-clink-clink" sound effect here.)

CBS Radio's "Jack FM" stations in New York, L.A., Chicago, Dallas and Minneapolis will go commercial-free for 24 hours on Sunday, Jan. 15, to promote the season premiere of Fox's "24."

"The guys from Infinity (now CBS Radio) came to us and said, 'We've got Jack stations and you've got Jack Bauer, doesn't it make sense to do something together?' " says Kaye Bentley, Fox senior VP of national media/affil marketing/on-air.

The two sides came up with a plan for Fox to underwrite 24 hours of Jack programming. (24 as in "24" -- get it?)

Negotiations centered on the cost of a full day in five markets; Bentley calls it "substantial" but feels she got a good deal.

Throughout Jan. 15, Jack listeners will hear nothing but music -- and the station's Jack voiceover subtly promoting Fox and "24."

"It's a small component (of our campaign), but we always try to do a fun element," says Bentley. "This and 'American Idol' are our big deals, and you'll be able to tell that."

Evan Jacobs