The Doctor (Matt Smith), companions Amy (Karen Gillan) and Rory (Arthur Darvill), along with River Song (Alex Kingston) and ex-FBI agent Canton Everett Delaware (Mark Sheppard), escape the girl in the spacesuit and turn to tracking down the evil Silence, who have the power to make people forget they exist when not looking at them. The Doctor programs the Apollo 11 module as part of his plan. Canton and Amy search orphanages in Florida to find out where the girl came from. The Silence kidnaps Amy and takes her to an underground control room. Canton shoots and wounds one of the Silence and the Doctor learns about them.

Analyzing the spacesuit, River realizes that the girl must have had incredible strength to escape from it, and that the phone calls to Nixon in her voice were made by the suit itself. The Doctor learns that the Silence has been controlling humanity by guiding their technological development for thousands of years. Canton interrogates the captured Silence member, who mocks him for treating his wounds when humanity really should kill them on sight. Canton records this on Amy’s mobile phone.

The Doctor tracks Amy and materializes the TARDIS in the Silence’s control room. As the live broadcast of the moon landing appears on TV, the Doctor inserts the recording of the Silence member saying, “You should kill us on sight,” into the footage when the whole world is watching. The group leaves in the TARDIS while River kills the remaining Silence. The little girl, wandering in an alley, begins to regenerate, revealing that she is a Time-Lord.

The episode received generally favourable reviews, though there were complaints that too many questions were unanswered. The Silence was praised as nightmarish, creepy, and just plain weird. When the Silence costumes interfered with the actors’ sight, they had to be guided like the blind. The Silence’s time engine was used in The Lodger episode. In this episode, River Song and the Doctor kiss. River Song takes a wonderful leap off a building, through the open TARDIS doors, into the swimming pool. Canton was forced to resign from the FBI because he wanted to marry a man. A mysterious character named Madame Kovarian (Francis Barber) appears to Amy in this and several episodes. Her eyepatch was inspired by Emilio Largo in Thunderball.