The Ninth Doctor, Rose, and Jack are cornered in a London hospital during the Blitz by patients wearing gas masks fused to their faces asking for their "mummy". The Doctor pretends to be the “mummy” and orders them to go back to their room, and the patients shuffle off. Jamie, the index case of the "epidemic", also responds to this, leaving his sister Nancy alone. The Doctor, Rose, and Jack investigate the hospital room Jamie was treated at, and learn from recordings that the child is growing stronger with its powers and may become unstoppable. Jamie arrives shortly thereafter, having returned to "his room", along with other patients. Jack teleports himself, the Doctor and Rose to Jack's spaceship. The Doctor uses the ship's Chula nanogenes to heal his wounds while learning more about Jack's past.