It’s hard to believe that it’s taken until now to get two such redoubtable actors onto Doctor Who (not counting Warner’s voice role in the show’s Uncanny Valley adventure, ‘Dreamland’), and it’s almost a shame that they had to appear in this episode. Not that Mark Gatiss’ taught script doesn’t serve them well – it does – but because the focus is less on the Red Menace, and more on the menace from the Red Planet.

‘Cold War’ has a singular aim of doing for the Ice Warriors what Series 1’s ‘Dalek’ did for Skaro’s trundling action figures. And it accomplishes it with military precision.

Comparisons with ‘Dalek’ aren’t unfounded. There’s a claustrophobic setting, a relatively new companion, an unstoppable monster that The Doctor has a history with… and, rather than overwhelming us with massed ranks, ‘Cold War’ distils the raison d’être of an entire alien race into the actions of one bellicose beast. Pay attention ‘Rise of the Cybermen’, ‘Sontaran Stratagem’; this is how to reintroduce a classic foe.

Still the familiar Ice Warrior of the Troughton era, the monster’s been given an upgrade for the HD age. It’s a formidable construction of CGI and costume design, but also good old-fashioned rubbery effects work. The kind that’ll send a nostalgic pang through the hearts of many a fan who watched the show in the 60s.

While the Ice Warriors always looked like their costumes were about to drop off in a chilly breeze, the 21st century model is more akin to a Martian Iron Man. Moving like a juggernaut through a script filled with love for the show’s history (watch out for fan-pleasing references to ‘The Krotons’ and ‘Forest of the Dead’), it feels as if The Doctor is fighting a tank on a submarine. A crafty tank. From Mars. Sold yet?

It’s easy to describe ‘Cold War’ as the essence of every submarine film you can imagine, hermetically sealed into 45 minutes – at times you almost expect Gene Hackman to appear by a bulkhead and start growling about Lipizzaner Stallions – but it’s more than that. Maybe it’s the foe, maybe it’s the corridors, or maybe it’s the Jon Pertwee-ness that Gatiss’s writing always infuses The Doctor with, but ‘Cold War’ feels like a solid slice of classic Who.

And frankly, if Gatiss ever wants to bring another old enemy back – even The Candyman, perhaps aboard a runaway zeppelin about to crash into a chocolate factory – then based on this episode we’d trust him to do it. Because as our old friend the Ice Warrior would hiss, ‘Thissss issss impressssive.’

Airs at 6pm on Saturday 13 April on BBC One.

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