The episode begins with the Toymaker’s neat precis of what is going on, and what is at stake: he plans to turn Steven and Dodo into dolls, and trap the Doctor in his power forever. Having got that out of the way, the rest of the episode sees Steven and Dodo unravel last week’s cryptic clue to reveal the purpose of the second game: find the one safe chair, and avoid the six deadly ones.

This is a slightly more fun episode than the last because it has the feel of an escape room, with a clue and props to help solve the puzzle. It also pits Steven and Dodo against a more interesting pair of opponents than last time: the King and Queen of Hearts. They’re an amusing pair – the King, a slightly absent-minded, but conniving old duffer, and the Queen haughty and condescending. She calls Steven and Dodo peasants, and channels Lady Bracknell when it’s pointed out she’s a playing card. There’s also an interesting hint of their sad backstory: ‘We are victims of the Toymaker, the same as you are.’ They are the horrible fate that awaits Steven and Dodo if they get it wrong.

While Steven is his usual dependable self, albeit with a streak of ruthless self-preservation that’s not shown itself so nakedly before, Dodo’s character is as changeable as her accent. One moment she’s smart enough to warn Steven not to sit in any of the chairs, then a few minutes later she’s naively forgetful of the danger, revealing the game plan to the Hearts and needing to be reminded that ‘it’s not a children’s party.’ Bizarrely, she also just sits in one of the chairs and nearly dies.

That scene is particularly poor: having deduced a way to win the game, in the end Steven and Dodo’s success comes down to a cheat – Dodo rescued from being frozen to death in one of the chairs, when all the others seemed to be inescapable – and on the Hearts making an uncharacteristic, if touching, suicide pact: ‘If we go, we go together.’

Elsewhere, the Toymaker removes the Doctor’s power of speech – which also removes the idea that this episode could be a battle of wills between them given one of the participants is both invisible and inaudible. In fact, Michael Gough has little more than a cameo, and his ‘battle of wits’ with the Doctor amounts to watching the counter for the Trilogic Game.

Fortunately, the photographs suggests this must have looked impressive, particularly the Hearts’ costumes, and the creepy, inanimate dolls that suffer imaginatively gruesome fates in the deadly chairs – including electrocution, dismemberment and crushing – that must have given the more morbid children something to enjoy. And there’s a very nice touch at the end of the episode when the Toymaker uses TARDIS phone to relay the next clue, and Steven and Dodo set off into the next game zone…

Next episode: The Dancing Floor