Let’s start with Jo Grant. A couple of years back she turned up in The Sarah Jane Adventures where she was reunited with the Doctor, as played by Matt Smith. While catching up on an alien planet, he lets slip that he’s travelling with a married couple, the Ponds. Jo is taken aback. “I only left you because I got married,” she pines.

She’s alluding to an unstated fact about Doctor Who, at least up until the Matt Smith era. That for a companion, finding someone you want to spend your life with meant the end of your TARDIS travelling. Getting hitched meant staying behind with someone, not dragging them along. Which was kind of understandable if one viewed Doctor Who, at least in part, as a kids’ show. Because marriage brought with it the implication of sex, and although the series might occasionally invite speculation on how its main characters ate and went to the toilet, any thought of which TARDIS bedrooms saw some action was right out.

New Who, though, has no such hang ups. Since 1996, Doctor Who has had romantic relationships at its, um, heart. The Doctor has been shown to be someone who loves and who is loved. He has had a string of love interests, not least of all his companions like Rose and Martha, if not Donna. But marriage (or its de facto equivalent) was still the end of the line for a companion, even in the Russell T Davies era; Rose is paired off with the one-hearted Doctor, Martha marries Mickey and Donna marries Shaun.

What, I imagine you’re saying by this late stage, does any of this have to do with The Girl Who Waited? Only that watching it got me thinking about marriage in Doctor Who and specifically, that since Steven Moffat took over as showrunner in 2005, the subject of marriage – once used only as a way of exiting companions from the show – has been embraced. He’s placed two marriages centre stage: the Ponds’ and the Doctor and River’s.

The topic of the Doctor and River’s unorthodox union can wait till another day. The Girl Who Waited is concerned with Amy and Rory’s relationship, and while that’s not unusual in itself, it’s a story where them being a couple is essential.  In the episode, Amy gets trapped in Two-streams, a medical facility, and only Rory can rescue her. This is ostensibly because the Doctor cannot leave the TARDIS for fear of being infected with a Time Lord specific illness. But the quarantining of the Doctor feels tangential.  Of course Rory would dive into Two-streams to rescue her, as Orpheus dived into the underworld, simply because he’s her husband. That’s his job. And that’s the nuance which comes with married companions, that you wouldn’t get if this was, say, first season Tom Baker and Harry had to rescue Sarah (or vice versa).

A subtext running through this season is that the Doctor is becoming more mysterious and less reliable.  And Rory and Amy react by relying on each other. In The Curse of the Black Spot, for instance, Rory specifically asks Amy to perform CPR on him, because he trusts her (not the Doctor) to never give up.  And Amy’s opening monologue in A Good Man Goes To War is all about her faith that Rory (not the Doctor) will come for her and Melody. Having companions married to each other offers a new dynamic; their relationship with each other is more important than their relationship with the Doctor. He will always be an outsider.

A central premise of The Girl Who Waited is ‘will you still love me when I’m 64’ (or how ever old Amy ends up being), with the added sci-fi twist that Rory is still young. Rory, being the thoroughly decent chap that he is, of course stays loyal to older Amy. But then there’s the added complication when the Doctor manages to fold time back on itself (or something) and young Amy appears alongside old Amy. Rory very quickly decides he wants to save both versions of his wife, which is touching and again what a loyal husband, who loves his wife at any age, would do.  Allowing a married couple on board the TARDIS has enabled new types of stories – like The Girl Who Waited – to be told.

The Doctor meanwhile is kept on the sidelines. Well, it’s a Doctor-lite episode after all. But there’s enough of him in the story to show a new, devious side of the Eleventh Doctor. When older Amy declares that she wants both versions of herself saved, the Doctor says this is possible. This spurs Rory and the Amies into action, helping motivate them to outfox the handbots and fight their way back to the TARDIS.

But the Doctor is being crafty. He knows it’s impossible to recue both versions of Amy. Does he lie to Rory and Amy to make sure they get safely back to the TARDIS? It’s left unconfirmed, but it certainly seems that way. If so, the Eleventh Doctor has manipulated his companions as effectively as the Seventh Doctor did Ace. Writer Tom MacRae has written about his admiration for the McCoy years, so drawing parallels between these two Doctors seems deliberate.  But maybe not – after all the Moffat years have clearly established that rule one is ‘the Doctor lies’.

And his lie here leads to a great climactic moment in The Girl Who Waited, where older Amy and the Doctor see each other for the first time. In that moment – a triumph of Smith’s acting and Nick Hurran’s direction – it’s clear that now Rory and young Amy are safely on board, the Doctor is going to lock old Amy out of the TARDIS. She realises it and runs, but of course she doesn’t make it. Those Prussian blue doors slam shut.

Rory is outraged, but the Doctor is resolute. He hands the decision over to Rory, seemingly as a way of assuaging his own guilt. He says to Rory they can only take one and puts his hand on the lock, forcing Rory to make the decision.  It’s a devastating moment, and Arthur Darvill plays it brilliantly. “You’re turning me into you!’,” he bawls at the Doctor. But the door is locked and Rory and older Amy can only press their hands together on either side of the police box’s windows before the end comes.

The classic series of Doctor Who­ did love stories, but it did them pretty poorly. Jo Grant, for instance, fell in love over the course of a handful of episodes and married a man she hardly knew. Other companions fell in love far more perfunctorily than that.  If there’s one aspect in which the new series far exceeds the old, it is in its ability to tell love stories. And with a married couple on board it can tell different types of love stories. We don’t waste time seeing Amy and Rory fall in love, they already are in love. And as The Girl Who Waited shows, that brings a whole new set of complications.

LINK to Logopolis: In both stories, one of the regulars meets a future version of themselves.

NEXT TIME: You must think my head zips up the back! It’s tea and fruitcake and the Image of the Fendahl.