Most episodes of 24 feature their share of action – it is, after all, an action show – but every now and then you get one that steps things up a notch, and this is certainly one of them.

After quickly establishing that her daughter is in custody, Margot coldly decides to turn on her before she can reveal anything to Jack and the authorities. Margot is clearly insane, and her inflexibility in understanding her daughter’s family loyalty – surely a trait that she should admire – may cost her everything. Simone didn’t want to kill her niece (fair enough!), but she was never going to give her mother up – at least not until she started trying to kill her, any way!

Margot points her captured drone at the hospital Simone is in, and let’s rip. The hospital evacuation is as exciting as it is gruesome: the shots of the walking wounded emerging from the chaos, missing limbs and covered in rubble, have definite shades of 7/7 about them.

An attack on the hospital might have been big enough, but then it’s followed by the ludicrous car-chase through the streets of London, as Jack tries to outrun and evade a military drone with a full complement of missiles. It’s a wonderfully high-concept sequence, and it’s thrillingly executed by long-time 24 director Jon Cassar. It should also raise the stakes of the season now that London has been attacked, and the threat is openly out there.

Elsewhere and it turns out that Navarro is in league with Chloe’s freedom of information boss Adrian Cross, in a twist that it wasn’t hard to see coming, given what a shifty, gravelly performance Michael Wincott has been giving all season. CIA analyst Jordan, meanwhile, has been sniffing around data that could lead to the exoneration of Kate’s husband, so Navarro sends him down to Camden Lock to take a bullet. (If you didn’t yell “JORDAN’S ALIVE!” as he clambered out of the canal at the episode’s end, than you’re doing it wrong.)

There are also strong scenes between President Heller and PM Davies, with Heller coming to concede that he may have to step down due to his health issues. In light of that, is he about to surrender to Margot, or does he have another play at work?

Heller is a strong character, and William Devane one of the show’s better performers, so it’ll be interesting to see if he can navigate his way out of the day alive. In other news, chief of staff Boudreau has run afoul of the Russians for forging Heller’s signature, but the most interesting part of this plot so far is the presence of the Russian’s baffling moustache.

On the whole, this is a great episode (penned by What Remains and Inside Men writer Tony Basgallop), dominated by the sort of outrageous action sequences that only 24 can muster.

The show can’t depict high-concept lunacy like this every week (for budget reasons, as much as plot), but it’s always good to see the show having fun, throwing caution to the wind and flexing its action chops once in a while (if you can call decimating the streets of London with missile attacks fun!) That all the craziness is complimented by strong character work with Heller keeps the episode balanced, and Live Another Day continues to be hugely entertaining.

Aired at 9pm on Wednesday 11 June 2014 on Sky1.

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