The episode starts with the Doctor traveling back to 1981 to witness the chance meeting of Clara's parents, then progressively forwards, as he watches her grow up. Two items come into to play during this sequence; the leaf (the most important leaf in human history) and the book that she keeps it in (101 Places to See).
Then the Doctor is in the TARDIS and traveling back to the next morning, from where we left off at the end of The Bells of St. John. He brings Clara aboard, and she fires a round of questions and when he fires back, "Where do want to go?" she doesn't have an answer, she ends up saying that she wants to see something awesome .
They end up on The Rings of Ahkaten, an asteroid belt, looking at a pyramid on one asteroid, while another is full of a city and marketplace . While exploring the Doctor runs off to get something from the TARDIS and Clara encounters a young girl on the run. Two priestly looking guys looking for her, call her the Queen of Years. Clara hunts the girl down and befriends her, when three creatures in black jackets and German WWII fighter masks appear from a purple smoke. Clara takes the little girl (Merry) back to the TARDIS to hide, but she can't get in so they hide behind it. Clara explains a time that she, as a young girl was scared and her mom helped her through it, in doing so Merry is calmed and ready to return to the task she is ordained to.
Merry sings a lullaby to Grandfather (the old god), something goes wrong and Merry is tractor beamed to the Pyramid . The Doctor and Clara walk away to get a hover cycle (that looks like a leftover design of Dave Martin) and go after Merry.
They rescue Merry only to discover the threat isn't the alien creature kept asleep in a glass box by lullabies, but in fact a God within the sun that the rings of Ahkaten orbit.
My prediction about this episode is that this God, is the Great Intelligence, and the Doctor's tactical error was in feeding his experiences to this God, and letting Clara give the Intelligence her Moms infinity of possibilities, in the form of the leaf that her dad saved (the most important leaf in human history).
On its own though, this episode really lacked story. I was impressed with the huge variety of alien species in the marketplace, but unimpressed with what was done with them, nothing. I was also unimpressed with the pyramid and the mo-ped, they lacked a wow factor. What really lowered the rating for me was the fact that the potential was there, it just wasn't executed. On a scale of 1 -5 I gave this episode 3, and it was close to only getting a 2.
Clara: We can go anywhere?
Doctor: With in reason. Well, I say reason.
Clara: So we can backwards in time?
Doctor: And space, yes.
Clara: And forwards in time.
Doctor: And space, totally. So, where do you want to go? Hey! What do you want to see?
Clara: I don't know. You know when someone asks you what your favorite book and straight away you forget every single book you've ever read?
Doctor: No. Definitely not.
Clara: Well that's a thing. That happens.
Doctor: And, back to the question
Clara: Okay, So... so, so. So, I'd like to see. I'd like to see. What I'd like to see is, something awesome.
Clara: You've been here before?
Doctor: Yes, yes, yes I came here a long time ago, with my grand-daughter.
Doctor: Listen. There is one thing that you need to know about traveling with me. Well one thing, apart from the blue box and the two hearts. We don't walk away.
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