With "The Time of Angels" Steven Moffat took quite a gamble by bringing back two of his best-loved Doctor Who creations: the Weeping Angels and River Song. In reintroducing them to the Doctor, both at the same time, he risks diluting their impact on fans, especially given that "Blink" is widely regarded as one of the best Doctor Who stories of all time, and River Song was already one of the most beloved characters after her one appearance. That's a high stakes game, and even more so when you consider this is only his fourth story as Doctor Who showrunner.

Thanks to some inspiration from his favorite science fiction movie franchise, his gamble paid off handsomely.

Here are some things to keep an Angel eye out for, the next time you watch:

(The episode is available on iTunes and Amazon.)

This was the first story to be filmed for Season Four, and as such, this episode contains the first scenes of the Eleventh Doctor in his new incarnation, with his new companion (who had only recently been renamed Amy Pond, changed from Lucy Sparrow). If you look closely at Matt Smith's hair, you can see it is at least two different lengths during the episode.

When writing the story, Steven Moffat decided to model it on Aliens, the more gung-ho and soldier-packed sequel to the more somber Alien. In a blog for the BBC, he described Aliens as "the best conceived movie sequel ever," and used it as a way to prevent the return of the Weeping Angels suffering from a form of diminishing returns:

"Good Doctor Who monsters have to come back — it's a rule. But my feeling is that you always have to bring back a monster and do something different with it. So although Blink was a very popular episode, it was also a very spooky, cerebral episode. These Weeping Angels episodes are really the polar opposite, these are like a big action movie — albeit an action movie with bad guys that can't actually move! It's a very different feeling."

The script has no mention of River Song landing on top of the Doctor when she enters the TARDIS from the escape hatch of the Byzantium. That moment of physical comedy was Matt Smith's idea, and proved quite tricky to shoot.

The Alfava Metraxis scenes, next to the Byzantium, were filmed at Southerndown beach, Vale of Glamorgan, better known to Whovians as Bad Wolf Bay.

The moment where an over-cocky Doctor rips a strap off the ceiling of the inside of the small ship was derived from a real moment, when Matt Smith did exactly the same thing. The team liked it so much they reshot it.

The dazed security guard who had fallen prey to River Song's lipstick was played by the British rapper Mike Skinner, who recorded and released music as The Streets. Adam Smith, who directed this episode, had previously made pop videos for the band and knew he had the right look for the part.

https://www.youtube.com/watch?v=3Qg3rQfeZv4

According to the DVD commentary for this episode, the segment where River Song flies the TARDIS, complete with the complaint that the Doctor leaves the brakes on — a firm fan favorite — was added at the last minute as, due to heavy rainfall, three pages of the script had had to be abandoned at the beach location used for the scenes when the Doctor, Amy and River first arrive next to the Byzantium.

The scene in which the Doctor visits a museum to look for historical errors is a callback to "An Unearthly Child," the very first episode of Doctor Who, where Susan Foreman, the Doctor's granddaughter, does the same thing with her history text books.

Similarly, when the Doctor rushes to leave the TARDIS without checking the environment outside, it's a reference to a similar scene in "The Power of the Daleks" when the Second Doctor, who has only just regenerated, is stopped by a confused Ben and Polly who try and stop him because he hasn't checked where they've landed. His reply: "Oxygen density 172, radiation nil, temperature 86, strong suggestion of mercury deposits. Satisfied, Ben? Now, are you two coming or are you not?"

There was a bit of a problem around the last seconds of this story when it was first broadcast in the U.K. As is common practise in TV, a likeable cartoon ident for the next show appeared at the bottom of the screen. It was the talent show Over the Rainbow, hosted by Graham Norton.

Trouble is, the end of this episode is a cliffhanger:

https://www.youtube.com/watch?v=BDLX5c6FymE

And what British viewers saw, during that intense speech, was this:

[caption id="attachment_394207" align="aligncenter" width="500"] (Photo: BBC)[/caption]

Which caused enough fan kickback it was even reported on BBC News. Graham Norton later joked about the situation:

https://www.youtube.com/watch?v=VnpZS_54uoA

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