Science Man takes them to Elliot, explaining that he doesn't vivisect them, just store them: "I took samples of the young, slowed their lifecycles to a millionth of their normal rate. So I could study how they grew, what they needed, how they lived on the surface." Awake, with his family, through millennia, and then for the last 300 years, just him. For some reason this causes the Doctor to just fall in love with him, but I've been trying to figure out why forever and I still have no idea. It's just stupid and shitty: "I've been kidnapping people for thousands and thousands of years and cutting them open while they screamed -- but the kids I just put in a dreamless death state and stared at them while their bereft parents wondered where their children had gone." That is adorable!
Mo wakes up Elliot and explains how they're in the center of the Earth and there are lizard men, and the Doctor needlessly apologizes for letting him go get his headphones that one time, which Elliot gracefully and needlessly forgives, and everybody heads back to the dining room-slash-execution room-slash-tribunal kangaroo court room. They leave Science Guy back there for some reason, I guess in inverse parallel to Mack setting up the drill to come fuck with us later, as he notes the soldiers being woken up and goes down there to give Restac more grief.
Eldane says they've been waiting forever to return to their rightful place, that's like their whole point the last few thou, and Nasreen points out we're already over population up here, so why add another species? Amy's so bored she's nearly asleep. And in case you didn't understand what was going on, more dumb voiceover speechifying: "As I sat there that day across the table from the humans," he says, sitting across the table from some humans, "The future of both species and of our beloved planet Earth rested in our hands," he says, as they discuss the future of both species and Earth. "But as the discussions went on," he says, as they go on, "I began to despair about whether we would ever find any common ground," he says, as they pantomime an inability to find common ground.
"As ambassadors for our species, we all had too much to lose," says Eldane, and suddenly Amy perks up and sidebars with Nasreen, finally pointing out the shittiest possible areas of Earth: The outback, the Sahara, whatever. Nasreen is worried about them breeding. "And anyway, what benefit does humanity get? And how would we ever sell this to people on the surface?" The first question is uncool, but seen as part of the second question, it makes more sense. Eldane is also sort of rude: "If I could get a word in, maybe I could tell you. You give us space, we can bring new sources of energy, new methods of water supply, new medicines, scientific advances. We were a great civilization. You provide a place for us on the surface, we'll give you knowledge and technology beyond humanity's dreams." They all hug and dance around and say shit like "Now I'm starting to see it!" and "More similarities than differences!"