Whatever worries Kiefer Sutherland may have had about reprising the role of Jack Bauer in 24: Live Another Day (Sky1, Wednesday), learning his lines for episode one won’t have been one of them. After a four-year break, the show returned with its trusty digital clock standing at 11.00 a.m. — and, as ever, the events took place in real time. Yet it wasn’t until around 11.43 that Jack spoke his first words.

Not that, after four years of being hunted by the authorities for saving the world in too maverick a way for those pen-pushers in Washington, he was having an uneventful day. By the time he broke his silence with the command ‘Take me to her’, Jack had already been tracked down to an abandoned warehouse by a CIA team; beaten a few of them up; had a gunfight with the rest; raced through a crowded street-market leaving any number of scattered boxes in his wake; been arrested; been interrogated in a CIA centre; and — with his hands literally behind his back — knocked out the armed escorts leading him to the ‘Special Activities’ section for some proper torture.

All of which might have been enough for the first 43 minutes of some programmes. But not for 24. At this stage, other elements in the mix included worldwide protests against America’s use of drones, the growing power of China and, rather less topically, a US president in the early stages of Alzheimer’s.

After a couple of slightly tired series, and that four-year absence, such full-throated, old-school action came as a huge relief. This time, though, there’s also the fact that Live Another Day is set in London, which for British viewers adds a whole new layer of fun.

A few years ago, I suspect you could have got pretty good odds on Stephen Fry being among the cast of 24. Here, he shows up to give his usual American-fantasy-of-the-typical-Brit turn as the Prime Minister who’s trying to persuade Parliament not to close our US drone bases. And in Wednesday’s second episode, we even got a climactic shoot-out in the ‘projects’ of West Ealing, where cars full of CIA marksmen were held up only slightly by the speed bumps.

On a more traditional note, the new series sticks defiantly to the policy of ascribing implausible abilities to both computers and Jack himself. The ‘her’ he demanded to be taken to in Special Activities proved to be none other than Chloe O’Brian (Mary Lynn Rajskub), his most faithful supporter when he was first on the run from an ungrateful America. Since then, she’s become a Goth and Snowden-like whistle-blower — which is why Jack found her strapped to a torture table. Luckily, he knew precisely where in the CIA’s underground lair the two would be chased to, and so could get his accomplice to blast a large hole in the London tarmac above them for the purposes of escape.

Initially, it looked as if freeing Chloe was an act of simple altruism, as well as the reason he allowed himself to be caught in the first place. (Naturally, it takes more than the combined efforts of the world’s security services to capture Jack if he doesn’t want them to.) In fact, the real reason was so that he could follow her to her hideaway in the perhaps most technologically advanced squat in history — where, within the graffiti-covered walls, Chloe and her whistle-blowing chums have access to all the CCTV cameras in London, and all the intelligence traffic in the world.

Jack took a predictably stern line on the giving away of American secrets (‘You’re smarter than that, Chloe …there are agents dying in the field’). But he also knew that smacking these people around a bit represented his only chance of finding Derek Yates (Joseph Millson), a former colleague of theirs whose own computer skills meant he could control American drones from a West Ealing flat. His plan was to use one to kill the president, now in London on an official visit. ‘The Doomsday clock is set at a minute to,’ Yates triumphantly informed his mini-skirted moll. ‘The world is going to hell.’

Except that, in the last of Wednesday’s avalanche of twists, Yates’s brief reign as baddie-in-chief came to an end when he was stabbed through the ear by the moll in question. She then removed her blonde wig, dropped her all-purpose East European accent and rang her mum, a posh British woman who seems — for now at least — to be masterminding the whole operation.

Since 24 began in 2001, there have been plenty of American series that are more sophisticated, with greater depth of characterisation, more believable plotting and so on. Even so, when it’s at its best — and so far Live Another Day feels firmly in that category — I still can’t think of any that have matched it for sheer, flat-out excitement: the thrills both relentless and served up with a face as straight as Jack’s own.