Although best known for the barnstorming and emotional speech given by the Doctor towards the end, there's a lot to "The Rings of Akhaten" that rewards repeated viewing. It's always fun to see a new companion react to the reality of being somewhere far removed from their usual time and place, and to discover new alien races we've not seen before. This story has all of that, plus a space moped, a tomb on an asteroid and a great big singalong at the end.

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

(The episode is available on iTunes and Amazon.)

This is Luther creator Neil Cross's second script for Doctor Who. He was invited to write it after handing in "Hide", which appears later in this season. One of the reasons he took the job on was the chance to create a big community of alien races jumbled up together, like the Mos Eisley space cantina in Star Wars. And the space mopeds were inspired by the speeder bikes on Endor, in Return of the Jedi.

In order to fit in the early scenes with Clara's parents and early life, Neil had to cut down some modern-day interactions between Clara and Artie Maitland, one of the children in her care. The idea was that it would be this backstory—and the leaf—that would allow Clara to save the day, rather than the Doctor's store of memories.

During the opening scene, the Doctor answers the question "are you alright?" with four adjectives: "Fine. Marvellous. Refulgent. Possibly a bit embarrassed". Should you need to know, refulgent means "shining very brightly," as in, "Darling your eyes, in the moonlight, they are quite refulgent".

Clara refers to the sonic screwdriver as his spanner, the second time a companion has sardonically used the British term for a wrench. In "Smith and Jones" Martha asked the Tenth Doctor if he had a laser spanner, and he replied: "I did, but it was stolen by Emmeline Pankhurst, cheeky woman."

While attempting to convince Merry to leave the temple, the Doctor finds himself quoting Lewis Carroll's poem "The Walrus and the Carpenter" - "The elements came together and burst apart, forming shoes and ships and sealing wax, and cabbages and kings."

Carroll's original verse runs as follows:

"The time has come," the Walrus said,

"To talk of many things:

Of shoes and ships and sealing-wax

Of cabbages and kings

And why the sea is boiling hot

And whether pigs have wings."

Two things are used to show that the Doctor is visiting Clara's past in the year of 1981. The first is the comic the Doctor is seen reading at the playground: the 1981 Beano Summer Special. The Beano is the longest running British children's comic, having first appeared on 30 July 1938, and their Summer Special is an annually produced extra large edition, for holiday reading. The second clue is the music playing in the background, which is "Ghost Town" by the Specials, a No.1 hit in the UK that year.

https://www.youtube.com/watch?v=RZ2oXzrnti4

The name of the planet/creature Ahkaten was inspired between the Egyptian heiroglyph Akhet, which means "the place where the sun sets or rises", and the pharoah Akhenaten. In fact, the naming of the Sun Singers of Akhat comes from an earlier version of the script in which Akhat was the name of the planet.

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

Shortly after this, Clara's dad explains her fondness for kicking a ball about by saying, "She wants to be Bryan Robson!". Bryan Robson was a famous English soccer player, taking the midfield position. At the time the Doctor met Clara by the swings, he was playing for Manchester United and the captain of the England squad.

https://www.youtube.com/watch?v=HYmAxqG59l0

When Clara appears by the graveside of her mother, the headstone reveals that Ellie Oswald died on March 5, 2005. This is the date on which the Ninth Doctor first met Rose Tyler, during the Auton invasion depicted in "Rose." While there's no suggestion that Clara's mother died in the attack, it has also not been made explicit that she did not, which some fans are rather excited about.

The Doctor announces Clara's arrival back in her own time and space with a quote. "Home again, home again, jiggety jig" comes from the Nursery Rhyme “To Market, To Market”, which dates back to the 15th century. First published in 1805 in a collection entitled Songs for the Nursery, the full lyric is as follows:

To market, to market to buy a fat pig;

Home again, home again, jiggety-jig.

To market, to market, to buy a fat hog;

Home again, home again, jiggety-jog.

To market, to market, to buy a plum cake;

Home again, home again, market is late.

To market, to market, to buy a plum bun;

Home again, home again, market is done.

To market, to market, a gallop a trot,

To buy some meat to put in the pot;

Three pence a quarter, a groat a side,

If it hadn’t been killed it must have died.

NEXT: "Cold War"

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