The Doctor. "This is the ultimate upgrade. Our greatest step into cyberspace..." It finally clicks: "Cybus." Horror dawns, and without stopping, he runs from the room.
Rose stands and watches the figures, moving like an army of ghosts in the light, and after ascertaining that good things don't come in those kind of numbers, she dashes back inside. The Doctor heads for her through the crowd and they run to the window, watching together as the monsters march. "It's happening again," the Doctor whispers. "I've seem them before. Cybermen." The Cybermen crash their fists through the windows, into the house. The party guests scream and cower as they are surrounded. The President's EarPod phone beeps, and he answers, sickened: "Mr. Lumic." Lumic cracks a joke on the line about crashing the party, and laughs wildly. "I forbade this," the President reminds him, and Lumic laughs again: "These are my children, sir. Would you deny my family?" (Parents and children, misshapen uneven imbalanced approximations, equations that don't quite fit, steel and cold where there should be warmth. And Rose is left alone.) "What are they?" asks Rose. "Robots?" Worse than that. The President asks who the Cybermen were. "Doesn't matter," says Lumic, and Rose's eyes go wide: "They're people?" They were, he explains: "Until they had all their humanity taken away. It's a living brain jammed inside a cybernetic body. With a heart of steel. All emotions removed." Why no emotions? "Because it hurts." I take it back. The Cybermen are a million times worse than the Dalek. At least the Dalek are doing what they're supposed to be doing, assuming they don't get all human-tainted and start worshiping false Gods. The Cybermen start out a perversion and just get worse. The President demands again to know who the Cybermen were. "They were homeless!" Lumic tells him. "Wretched and useless! Until I saved them, and elevated them. And gave them life eternal." We've already talked about that sufficiently, I think. "And now, I leave you in their capable hands. Goodnight, sir. Goodnight, Mr. President."
Lumic hangs up, and one of the Cybermen squares itself up in front of the party: "We have been upgraded." The Doctor asks into what exactly. "The next level of mankind. We are Human Point Two. Every citizen will receive a free upgrade. You will become like us." (That word again: free. Like the food at the dump.) "I'm sorry," says the President. Pity is the Bad Wolf of the season, but more now: pity for that which has been unnaturally extended. "I'm so sorry for what's been done to you," the President goes on. "But listen to me." Addressing everyone, he says, "This experiment ends. Tonight." Upgrading is compulsory, he is assured. "And if I refuse?" The Doctor interrupts him: "Don't." Even Rose is confused. Since when do you not tell the bad guys to fuck off? "What if I refuse?" asks the President again, and the Doctor steps forward to him: "I'm telling you, don't!" The President ignores him and asks a third time. "Then you are not compatible," the Cyberman replies. And then, the President challenges him: what happens then? "You will be deleted." The Cyberman grabs the President by the neck, and covers him in electric blue, and he dies. The guests resume screaming and running around. Peter calls Jackie's name, but he can't find her.