In the prelude, the clock is stuck at 5:02 PM in Area 52 and the leaders of The Silence are stuck in stasis. River Song is wearing an eyepatch like Madame Kovarian, as are Rory and practically everybody else. These eyepatches are actually visual communications devices.
The Doctor (Matt Smith) is aware of the time and place of his coming death. He wants to learn about The Silence to learn why he must die. He has no regenerations left. He meets the shape-shifting robot called the Teselecta and its miniaturized crew posing as one of The Silence, and they offer their help. He is led to Gantok (Mark Gatiss), another Silence member, who takes him to the blue living head of Dorium Maldovar (Simon Fisher-Becker) in a catacomb.
Dorium reveals that The Silence are dedicated to averting the Doctor’s future, warning him that silence must fall when “the first question” is asked on the planet Trenzalore. To avoid crossing his own time-stream, the Doctor gives the Teselecta four invitations to Lake Silencio in 1969, to pass on to Amy (Karen Gillan) and Rory (Arthur Darvill), River Song (Alex Kingston), Canton Everett Delaware III (William Morgan Sheppard), and a younger version of himself.
The Doctor comes to Lake Silencio, Utah, to meet his death by a younger version of River, who is being forced to kill him in the automated spacesuit built by The Silence. River surprises the Doctor by draining the spacesuit’s weapons systems and averting his death. Time becomes stuck as a result and begins to disintegrate. All of history begins to run simultaneously.
On the stuck Earth, Amy takes the Doctor to Area 52, a pyramid base where The Silence are contained in water-filled cells and Madame Kavorian (Frances Barber) is held hostage. River is also there. Aware of the consequences of her actions, she refuses to let the Doctor touch her, which would return Time to normal and the Doctor would die at Lake Silencio. Awakened by the Doctor’s presence, The Silence escape their cells and attack the troops defending the pyramid. Amy allows Kavorian to die as revenge for the kidnapping and brainwashing of her daughter River.
The Doctor and River escape to the top of the pyramid followed by Amy and Rory. The Doctor marries River and whispers to her to look him in the eye. There she sees that he is miniaturized inside the Teselecta ship disguised as his body and will not actually die if Time is restored. He asks her to go ahead and shoot him to prevent the destruction of the universe. They seal this pact with a kiss. Time moves forward and the status quo is restored. Later, River visits Amy and Rory to tell them that the Doctor is still alive. Elsewhere, the Doctor explains to Dorium that his revealed death will allow him to be forgotten, as he was attracting too much attention. Oh, and the great question that must not be answered? Doctor who?
There is mention in the story of the death of Brigadier Lethbridge-Stewart, actor Nicholas Courtney having just died in February 2011. The story received excellent reviews, though the “Star-Trek Reset Button” ending was criticized. Some of the plot didn’t make a lot of sense because writer Steven Moffat was busy writing the Sherlock series. River’s Theme morphed into Here Comes the Bride. Several characters from other episodes appeared: Charles Dickens, a Dalek, Holy Roman Emperor Winston Churchill, with the Silurian scientist Malokeh his physician. Amy draws the Krafayis, a Weeping Angel, the Satornyns, the Silurians, the Daleks, and herself as a pirate. She is somewhat protected from Temporal Change by her long-term exposure to the crack in the universe. Events from the entire season and more are tossed in to keep the roller-coaster going. God help you if you missed any episodes. But it’s a thrilling and exciting ride.