To tie in with the back-to-back airing of the entire first season of 24 on Friday, October 5 on FX, Cult Spy explores several components that made the venture so memorable and exciting.

For old fans this is the chance to relive the tension and twists of where it all began. For newbies, it's an opportunity to become acquainted with Mr Jack Bauer and his heroism. There's no turning back.

Although 24 didn’t initially garner huge ratings when it debuted on Fox in the States and BBC Two in the UK, its immense cultural impact soon became felt. With the innovative use of 'real-time' spanning across the season, 24 had a distinctively gritty tone, despite the obvious plot contrivances (although comparatively, Prison Break makes it seem like a fly on the wall documentary).

Stylistic devices like a ticking digital clock enhanced the sense of pressure for the viewer, while the split-screen allowed us to follow multiple narrative strands simultaneously. This may seem old hat now, but back in late 2001 when Day One was first shown, this was fairly groundbreaking stuff for a primetime US show.

WARNING: If you're not familiar with the events of Day One then do not read on if you want to be spoiler-free.

The Premise

Set around the day of the Californian presidential primary, Counter Terrorist Unit agent Jack Bauer battles to fend off a threat on Senator David Palmer's life. The plot thickens when the terrorists kidnap Jack's family and threaten to kill them unless he assassinates Palmer himself. As the day continues, the real villains behind the fiendish plan emerge, as does a double-dealing mole within the confines of CTU…

The Hero

Jack Bauer conveyed an appealing combination of phenomenal survival skills, brutal killing abilities and a genuine compassion for the lives of the innocent. There was a certain flawed element to his persona too, as evidenced by his strained family life and affair with fellow CTU agent Nina Myers.

In the role, Kiefer Sutherland generally alternated between an angry, shouty voice and soft whispering, like a car with only a first and a fifth gear. Still, it works! Don’t forget that Jack wasn't working alone. There was Tony Almeida and his legendary goatee on hand to help out too.

The Villains

Throughout Day One, we learnt that behind every great villain lies… an even bigger baddie! It was like one of those Russian dolls where inside lies another one, then another one. Initially, NAVY Seal turned mercenary Ira Gaines was the man that Jack had to foil, but it was eventually revealed that Serbian siblings Andre and Alexis Drazen were bankrolling the entire project and were out for revenge on Bauer for killing their evil father.

BUT – their daddy Victor wasn't really dead. Instead, he was holed up in a top secret prison and the real mastermind was quickly broken out by his sons. But once those villains were dispatched by Jack, the most evil character of them all was soon revealed in shocking circumstances. Step forward Miss Nina Myers…

Kidnapping Kim

"Is it a bird? Is it a plane?" they used to say about Superman. But Jack's daughter Kim, played by pin-up Elisha Cuthbert, effectively had her own spin on this saying. "Is she kidnapped? Is she in peril? Is she missing? Is she targeted by a terrorist cell?" The answer was a resounding 'yes' throughout the first season, as her character seemed to be on an endless loop of escaping captivity only to be captured again. Still, nothing compares to the cougar incident she encountered in the next season!

The Twists

Day One of 24 really upped the ante where plot twists were concerned – both in terms of their shock impact and sheer number. The most startling of these occurred when the seemingly benevolent CTU agent Nina Myers, whom Jack had done the dirty with behind his wife's back, was revealed to be the mole feeding information to the baddies. From then on, in subsequent seasons of 24 and similarly themed shows, viewers were VERY cautious when it came to trusting characters and their motivations.

The Legendary Guest Stars

Cinema legend Dennis Hopper was in fine form as the maniacal Victor Drazen, who cropped up unexpectedly and to great effect in the final few hours. But the real star cameo came from Kiefer Sutherland's one-time wingman Lou Diamond Phillips from the Young Guns films, as an ill-fated prison guard.

The Shock Ending

Viewers were forced to scoop their jaws up off the floor when a shocking murder occurred in the dying moments of Day One, when everything was seemingly wrapped up for the season. To read more, check out Cult Spy's Classic Moments.