After five years of hosting a show with no band, a limited budget, and ratings that wouldn't rise if Arnold Schwarzenegger came on to declare a run for president, Craig Kilborn announced he'd had enough of late-night TV. His last ''Late Late Show'' is scheduled to air Aug. 27 on CBS. ''I felt like I did all I could do for that particular show,'' says Kilborn, who insists his leaving is a purely creative decision, though insiders say he's been trying -- unsuccessfully -- to increase his $1-mil-plus annual salary. In Kilborn's favor: His show routinely beat ABC's ''Jimmy Kimmel Live.'' But he also trailed NBC's ''Late Night With Conan O'Brien.'' ''At that time of night,'' he says, ''you can't [do much to] change the ratings.''
But Kilborn's move might just change late-night TV in a way his Five Questions never did. Talk in Hollywood says the search for his replacement could have a domino effect on David Letterman, O'Brien, and Kimmel. ''There's only a few places [these hosts] can go,'' says Kilborn, who's mulling a career outside Hollywood (''coaching high school basketball,'' he jokes). ''I don't handicap what's going to happen.'' Fortunately, plenty of others do.
One popular theory holds that CBS and David Letterman's Worldwide Pants (which produces whatever show is in the 12:30 a.m. time slot) are essentially shopping for Letterman's heir: Think of ''The Late Late Show'' as a big ''Break in Case of Retirement'' glass case. But Pants' Rob Burnett says no one should expect to commandeer Dave's chair anytime soon: Letterman, under contract through 2007, ''is showing no signs of retiring,'' he says. ''He's in a rejuvenated period. I don't know why 12:30 after Letterman has to be viewed as any kind of stepping stone.''
The network has already gotten plenty of applications for the gig. ''We've been pleasantly surprised at the enormous interest,'' says Burnett. ''To go on after Letterman is a big deal.'' (Guest hosts will sub in until a permanent replacement is found.)
Of course, any new host will run into Kilborn's old problem: O'Brien. But some speculate that rival might be time-traveling himself. O'Brien has expressed a desire to try an earlier, more prestigious slot and frustration with Jay Leno's vise grip on ''The Tonight Show.'' With O'Brien's contract expiring in December 2005, NBC is gearing up for the possibility that Fox and ABC will offer O'Brien what he wants.
Fox won't comment, but a source says the net wants a marquee name like O'Brien to convince affiliates to give back the 11 p.m. perch once squandered on Joan Rivers and Chevy Chase. As for ABC, Kimmel's on his second exec producer and viewership is slightly down. Nevertheless, says ABC exec VP Andrea Wong, ''we have a late-night host in Jimmy Kimmel that we believe in.''
For his part, Kilborn doesn't get why anyone would want an earlier slot. He never did: ''There are advantages to 12:30. You can get away with more, be more experimental.'' Experimentation -- probably not the most enticing quality for a network with millions riding on late-night success.