By Peter Bowes
BBC News, Los Angeles
O'Brien (l) took over from Leno (r) as Tonight Show host in June 2009
It has been described as one of the biggest blunders in television history.
The US network NBC is embroiled in an increasingly acrimonious game of musical chairs involving its biggest star names, chat show hosts Jay Leno and Conan O'Brien.
The trouble started last year when the network moved Leno out of his long-time 2335 slot, on The Tonight Show, into prime time, at 2200.
The comedian's new programme, The Jay Leno Show, broke new ground for US TV since it aired at a time previously dominated by popular dramas.
Leno was replaced on The Tonight Show by O'Brien, in a move that was first announced by the network in 2004.
The switch around has been an almighty failure - with both Leno and O'Brien losing viewers in their droves. Now, NBC wants to put Leno back to his original time slot and bump O'Brien's show back to a 0005 start time.
No one is happy.
In an open letter, addressed to the "People of Earth," O'Brien said he would not play ball.
"I sincerely believe that delaying the Tonight Show into the next day to accommodate another comedy programme will seriously damage what I consider to be the greatest franchise in the history of broadcasting," he wrote.
"The Tonight Show at 12:05 simply isn't the Tonight Show."
Both Leno and O'Brien have used their comedy routines to express their anger at the network's bosses.
Leno's longtime rival David Letterman has also commented on the NBC row
Leno has quipped that NBC stands for "Never Believe your Contract".
He said critics of the war in Afghanistan were no longer referring to it as another Vietnam. Instead, they are calling it "another NBC". He also described the network as "America's most dysfunctional TV family".
O'Brien, potentially the biggest loser in the battle for talk show supremacy, got in a dig at his rival:
"I just want to say to the kids out there: you can do anything you want in life. Unless Jay Leno wants to do it, too."
The chat show drama has also provided another rival, David Letterman, with a rich seam of comedic material. Letterman's show airs at 2335 on CBS, and is currently leading the ratings.
"I'm fascinated by the situation over at NBC," Letterman said, describing "the bungling machinations of the idiots at the NBC executive level".
Letterman, who used to work for NBC, said the network was run by "pinheads," "nitwits," "twits," "knuckle-draggers," and "mouth-breathers".
The fiasco is enthralling a certain section of the American TV audience and media pundits because The Tonight Show is a national institution.
"Johnny Carson had it for many many years, and it was even an institution before that," explains Kim Masters, host of The Business on Los Angeles public radio station KCRW.
"There was a great clash of the comic titans when Johnny Carson left, between Jay Leno and David Letterman, and that's the thing Leno wanted, it's the thing Conan O'Brien wanted, it is a big deal."
Aside from the bruised egos, the talk show fiasco has financial ramifications for American television.
Like the US breakfast shows, late night television rakes in a lot of money for the networks.
"It is a little bit reminiscent of what happened with a version of Wall Street - it's the media world answer to that," says Ms Masters.
Kim Masters says Conan O'Brien has been sacrificed in the NBC fiasco
"They screwed up their own business so badly and now people are being sacrificed, notably Conan O'Brien, and while he may not be the average guy, he is the victim of a gigantic corporate screw-up that goes well beyond who is on when in late night, it goes to the whole business of network television."
The saga is far from resolved. NBC has confirmed that the The Jay Leno Show at 2200 will end next month and, after the Winter Olympics, it will be replaced with dramas such as Law and Order and Parenthood.
A new reality series, The Marriage Ref, which is produced by Jerry Seinfeld, will also debut in prime time.
The fates of Leno and O'Brien still hang in the balance.