Rather neatly actually airing between 9pm and 10pm on Sky1 tonight, we’ve reached the penultimate episode of 24: Live Another Day and, while it’s been an entertaining ride pretty much throughout its abridged run, it’s only in the past few weeks that the bar has really been raised.

It’s been the introduction of Cheng Zhi that has really given the series an injection of life and impetus. His mere presence adds gravitas to the plot in a way that the Al Hazari family never quite managed, as enjoyable as Michelle Fairley’s mad Margot was. Cheng’s history with Jack, Audrey and Chloe gives the show much higher personal stakes, and the plot he’s involved in – essentially starting World War 3 on behalf of the Russians – has far higher global stakes.

With a shorter run, at first it felt apt that the main plot felt somewhat smaller – a personal vendetta against President Heller – but these past few instalments have shown that even with a 12-episode order, the writers can still tackle a much bigger, increasingly world-threatening scenario. It’s difficult not to wish that this plot had been the entire focus of the season all along, but better late than never, I suppose.

There are several great moments in this hour:  Jack finding his way – too late – to the override device, and hearing a recording of Cheng’s voice, allowing for years of storytelling to pass across Kiefer Sutherland’s face, as Jack faces up to the unlikely reality of the situation. Equally good is the later moment when Jack and Audrey’s emotionally rich and raw phone call sees the often superfluous split-screen gimmick come into its own.

Elsewhere, Chloe makes her escape from Cheng and winds up lying in a ditch, while Mark Boudreau is finally outed as having helped the Russians access Jack. It’s about time that plot came to light, and it finally gives Tate Donavon something interesting to do, as he has to not only live with the choices he’s made, but attempt to justify them too. Boudreau had good intentions, but he might have inadvertently helped start World War 3. That’s an interesting place to put him.

Towards the episode’s end, the series seems to be subverting itself. Audrey meets with a hitherto unknown associate with links to China, and opens up a new angle to try and prevent any retaliation for the sinking of the Chinese carrier. In a normal length 24 season, this might have opened up a new plot thread – dare we say “filler” – for a few episodes, but here, with only one episode to go, there’s surely not enough time? And sure enough, the meeting ends with a shock as (in this week’s plot implausibility) Cheng somehow has a sniper targeting the meeting, and kills everyone but Audrey!

So, the Russian with the amazing moustache is dead, the race to catch Cheng is on, and all presumably relies on Chloe with the Dragon Tattoo finding her way out of that ditch and to Jack. And if the stakes of preventing World War 3 weren’t high enough, Cheng now has a gun aimed firmly at Audrey’s forehead. There’s a lot to deal with in the final episode, and one suspects Jack might have to make some difficult decisions before too long…

There’s also the promised time-jump to deal with next week, which they’re somehow going to have to make work within the confines of one episode. It will be the first episode in 24 history to cover more than a one-hour period, or to not occur fully in real time.

24: Live Another Day has been a successful experiment thus far, but how will this one last twist on the formula work? We’ll find out soon enough!

Aired on Wednesday 9 July 2014 on Sky1.

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