24: Is it all over for Jack?

The clock is ticking, and this time Jack Bauer really will be lucky to escape. After eight seasons and 192 hours of real-time drama, the daring action hero at the centre of 24 faces one group of adversaries who will always hold the upper hand: the men in suits at his TV network.

In a matter of days, Fox Television must decide whether to drop the show. And although secret agent Bauer tends to make a habit of upsetting the odds, the prognosis in this battle for survival does not look good.

The front page of Variety, the entertainment trade magazine, this week reported that 24's demise was imminent. The network appears "ready to end the long-running hit" because of falling ratings and rising production costs. A final decision over whether to make the current series the last will, it said, "be made in the next day or two".

Adding to fears of the show's demise was Fox's president, Kevin Reilly, who told an interviewer that he was not sure it had a long-term future after this season ends in June.

"It's a very tough call," he told The Hollywood Reporter, when asked if the show was to be axed. "It's a huge part of our legacy, and a show we're very proud of creatively. So it's not an easy call."

The show's final chapter would mark the end of an era. Launched in the wake of 9/11, its tub-thumping celebration of all-American derring-do made it perfect entertainment for a nation that had been thrust into the "War on Terror". President George Bush was famously said to admire Bauer, the dashing but psychologically troubled protagonist played by Kiefer Sutherland.

The show's "real time" structure, in which each one-hour episode followed the events over a fictional hour of time, was considered revolutionary.

But shifting public attitudes towards America's overseas adventures have left the programme feeling less in tune with the public mood, particularly outside the US, where it was widely (and very profitably) syndicated.

On Thursday, Baroness Manningham-Buller, the former head of MI5, even sparked controversy in a speech where she blamed the gung-ho attitudes fostered by the show for contributing to America's mistreatment of terror suspects.

"One of the sad things," about US policy, she said, "is that Cheney, Rumsfeld and Bush all watched 24." The former spy chief added: "The Americans were very keen that people like us did not discover what they were doing."

Yet the biggest factor contributing to the show's potential demise is almost certainly cold, hard cash. Normally filmed in Los Angeles, it is hugely expensive to make, and its cost per episode is rising thanks to growing wage demands from staff and stars, and expensive on-location shoots.

At the same time, audiences are down to below nine million from a peak of 14 million five years ago.

"Even though ratings are down, a show like this gets more expensive every year to make," said Michael Schneider, Variety's TV editor. "People's fees increase and production costs keep going up, so at some point a network will always say that the potential upside of replacing an old show with a new hit will outweigh the downside."

The uncertainty over 24's future comes at a torrid time for network TV drama, which in recent years has often been replaced by cheaper – and more popular – reality TV shows.

Though 24 was showered with awards in its early years, winning two Golden Globes and 18 Emmys, it has failed to make an impact lately. Awards shows are largely dominated by modish dramas such as Mad Men, made for cable channels.

Despite this trend, Mr Schneider believes that Fox will replace 24 with another drama, since it already has American Idol and So You Think You Can Dance, two of the nation's most watched reality shows.

Jack Bauer's one potential prospect for redemption may come in the cinema. 20th Century Fox, the network's sister film studio, recently hired Billy Ray, the writer of State of Play, to come up with the script for a 24 movie to be set in Europe.