The episode is built around three big sequences, one each for Hartnell, Hill and Russell. Hartnell’s scene is the comic highlight, and it comes when Robespierre summons Lemaitre away, giving the Doctor an opportunity to free Barbara and Susan, and escape Paris. To do so, though, he needs to trick the jailer into leaving Barbara’s cell door unlocked on the pretext that she will escape and lead them to her associates. The sequence is brilliantly written and acted, with the Doctor firstly manipulating the jailer into suggesting he lets Barbara escape, and then blaming the plan’s apparent failure on the jailer’s incompetence to the point where he has the man begging for his help in a cover up.

The comedy of this scheming is juxtaposed with the deadly seriousness of Robespierre’s conversation with Lemaitre. The paranoid Robespierre has become aware of a scheme by Paul Barrass to indict him, and declares that, ‘If this plot is successful, tomorrow, the 27th of July 1794, will be a date for history.’

History also looms large in Hill’s big scene. Informed of Leon’s treachery and death, she refuses to condemn him: ‘To his side, he was a patriot.’ Taking a wider view than Ian, who thinks Leon got what he deserved, she declares:

The revolution isn’t all bad, and neither are the people who support it. It changed things for the whole world, and good, honest people gave their lives for that change… You check your history books, Ian, before you decide what people deserve.

Given that a couple of months ago she was condemning and trying to destroy the ‘evil’ Aztec religion, this might either be seen as a bit of a volte face, or that her experiences in Mexico have helped Barbara develop a wider perspective on history. Regardless, it’s a scintillating moment, played with total conviction by Hill, and gives the episode, which is otherwise a bit lightweight, some moral heft.

This is in contrast to William Russell’s big scene, which is a shoot out in the crypt where he has been imprisoned. It’s another opportunity for Ian to be the brave, and slightly dull, hero, made more interesting by his sardonic revelation of the truth about his arrival in France. The sequence gives the episode some necessary action – when the rest largely consists of characters plotting with each other – but Russell again is getting the least interesting thread. Still, he fares better than Carole Ann Ford who gets seven lines, and is otherwise just there to use as a bargaining chip by Lemaitre against the Doctor.

The episode ends with the Doctor and Lemaitre, who have been circling round each other for a couple of weeks, finally speaking honestly. We still don’t know exactly whose side Lemaitre is on (we’ve seen he’s Robespierre’s trusted advisor, but we’ve also seen him keep the truth from the First Deputy), which gives the cliffhanger some tension.

Other things I noticed:

• Spooner is really bigging the Doctor up, in the same way the modern series often does. Ian and Barbara seem slightly in awe. ‘He’s dressed up as if he was running the revolution! From what I could gather, half the people there take orders from him,’ says Barbara. ‘I don’t know how he gets away with it half the time,’ Ian replies. Even the Doctor’s aware he’s becoming a legend, speaking about himself in the third person: ‘You can’t get rid of the old Doctor as easily as that.’
• After her earlier homesickness, Barbara says, ‘I’m so sick and tired of death, Ian.’ Perhaps another indication that the production team were still thinking seriously about whose contracts were going to be renewed for the next production block.

Next episode: Prisoners of Conciergerie

A Bargain of Necessity no longer exists. Not in any of its regenerations. This review is courtesy of the excellent Loose Cannon reconstruction