As a story, "Amy's Choice" has a very specific purpose, to show Amy the dark side of traveling with the Doctor on an emotional level, and to fully ignite (or re-ignite) her feelings for Rory. It also sets an unfortunate trend for Rory in that he dies, something he will become rather good at during his time in the TARDIS.

All this and Toby Jones too. Here are a few things to keep an eye out for, the next time you watch:

(The episode is available on iTunes and Amazon.)

Scriptwriter Simon Nye said he relied upon his own dreams for inspiration for this story, which was originally titled "The Dream Lord:"

"We've all had those moments, especially on waking, when you think 'Was that real, was that a dream?' Doctor Who plays with levels of reality and alternative universes, and the dream world is an alternative universe of sorts and all the more interesting for being a distortion or embellishment of our own waking lives. And the Doctor, being so mercurial and full of thoughts and intelligence, his dream life is particularly interesting and rich. He's especially freaked out by the idea that he should sleep at all – he sort of denies that that's the kind of thing he does – he's got too much to do and he's too wired. He's unnerved by the idea of dreaming himself."

The final title is a deliberate echo of Sophie's Choice, the William Styron novel—that was adapted for a hugely successful Meryl Streep movie in 1982 — about a Jewish mother in a Nazi concentration camp who has to choose between her two children, knowing the other will die.

The old people's home visited by the Doctor, Amy and Rory is named "SARN Residential Care Home." This is a double throwback, as Sarn was the name of the planet in the Fifth Doctor story "Planet of Fire," and also the name of a supporting character in the Seventh Doctor story "Time and the Rani."

https://www.youtube.com/watch?v=xhTAtgJ1n4E

Mr Nainby, one of the cast of attacking pensioners, is played by Nick Hobbs, who is not only an accomplished stunt man with an extraordinary range of experience — from Harry Potter and the Deathly Hallows to Avengers: Age of Ultron — he also made several appearances in Doctor Who during the early 1970s. He was the beast Aggedor in "The Curse of Peladon," appeared as various UNIT soldiers and was one of the Wirrn in "The Ark in Space".

The Doctor says he had an instruction manual for the TARDIS, but he throw it in a supernova because he "disagreed with it." This must have been after the events in the Fourth Doctor story "The Pirate Planet" (written by Douglas Adams), in which the Doctor is seen tearing a page out of a TARDIS instruction manual that caused him particular offense.

Amy's bitter jab at the Doctor — "then what is the point of you?" — is a line that links Doctor Who with Torchwood, and Sherlock too. It pops up in the Torchwood episode "End of Days," written by Chris Chibnall, with Gwen rounding on Jack to demand "There's something you can do, otherwise what's the f****** point of you!"

And in the Sherlock story "His Last Vow," an irritated Sherlock rounds on Mrs. Hudson to demand: "Then what, exactly, is the point of you?!"

It appears again in "The Impossible Astronaut," when the Doctor fires it back at Amy, and River and Rory, with "I'm being extremely clever up here, and there's no one to stand around looking impressed! What's the point in having you all?"

When the Dream Lord snipes at the Doctor in the butcher's shop, saying, "I bet you're a vegetarian!," it's an echo of the ending of the Sixth (and Second) Doctor adventure "The Two Doctors," in which the Doctor resolves to eat better in future. He says to his companion Peri: "From now on it's a healthy vegetarian diet for both of us," although he has been seen to eat meat many times since.

https://www.youtube.com/watch?v=VkhMH3xyPCE

Karen Gillan was particularly taken with her prosthetic pregnancy belly, and it actually changed her behavior for a short while, as she told the Daily Star: "I really enjoyed it – it was my favourite part of filming. I had a big bump. It felt ridiculous and it made me act ridiculously.

"It was fun but it really affected me. I became quite attached to it – I found myself rubbing it and it made me feel really mature. Everyone else was larking about like normal but I felt really old all of a sudden.”

The Doctor tends to carry a couple of other useful devices on his person besides his sonic, not least his stethoscope, which makes an appearance here for the first time since his regeneration. Rarely used for medical purposes, it first appeared as the Second Doctor attempted to listen closely to some pipes in "Fury from the Deep," popping up again in "The Space Pirates." The Fourth Doctor used it to examine Erato's spaceship in "The Creature from the Pit," while the Tenth listened to a door at the Thames Flood Barrier in "The Runaway Bride," and at the window of Adipose Industries in "Partners in Crime." He also whipped it out to listen to the walls of the shuttle bus he was trapped inside, in "Midnight" and even used it to track the signal from the Doctor's combined companions in "The Stolen Earth."

We shall see it again, in "The Lodger."

When the Doctor is rooting around under the TARDIS console, he opens a box, on which is printed the legend: "TARDIS. Time And Relative Dimension In Space. Build Site: Gallifrey Blackhole Shipyard. Type 40. Build date: 1963. Authorised for use by qualified Time Lords only by the Shadow Proclamation. Misuse or theft of any TARDIS will result in extreme penalties and permanent exile." There is a similar plaque on the console itself.

[caption id="attachment_396357" align="aligncenter" width="600"] (Photo: BBC)[/caption]

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