Due to the damage caused to the TARDIS from his regeneration, The Doctor finds himself hanging onto the entrance of the TARDIS as it flies over London. He eventually climbs back into the Tardis and collapses with exhaustion.

In a village a girl (Amelia Pond) is praying to Santa for help fixing a crack in her wall that she can hear voices from and asks for him to send help. As she finishes praying she hears the TARDIS materialise and sees it crashed on its side in her Garden having destroyed a shed. As she exits the house and approaches the TARDIS, the doors open and a wet Doctor climbs out and asks for an apple. Amelia then asks him if he came about the crack in her wall.

Amelia and the Doctor then spend sometime getting to know each other with the Doctor asking for and finding disgusting lots of different types of food until he gets fish fingers and custard. After a bit of conversation the Doctor says that Amelia is not scared of anything so it must be a very scary crack in her wall.

In Amelia’s room she gives the Doctor an apple with a face on and he investigates the crack in the wall. The Doctor then discovers that the crack in the wall is actually a crack in space-time and hears a voice saying Prisoner Zero has escaped. The Doctor then tells Amelia that the only way to close the crack is to open it which he does.

When he opens it a giant eye appears and sends him a message on Psychic Paper telling him Prisoner Zero has escaped before the crack closes. The Doctor then works out that Prisoner Zero has escaped through the crack, and starts to look around the house. Before he can do anything about it the TARDIS cloister bell starts ringing meaning he has to fix it, he then promises Amelia he will be back in 5 minutes but he does not return until a considerable time later. When the Doctor returns he rushes into the house telling Amelia to leave, he is then knocked out from behind by someone with a cricket bat.

At a hospital patients in a coma all start calling out Doctor. Later a nurse (Rory) then tells a Doctor that he has seen the patients wandering around the village. The Doctor doesn’t believe Rory and tells him to take some time off starting immediately.

At Amelia’s house, the Doctor finds himself handcuffed to a radiator with a policeman in front of her, when he asks for Amelia, the policewoman tells him she hasn’t lived there for 6 months. The Doctor tells the policewoman that he needs to speak to whoever lives in the house which turns out to be her, he then asks her to count the number of rooms on the floor which she claims is 5, the Doctor then points out it is actually 6. Despite his protests the policewoman then proceeds to enter the room.

As she is in the room the Doctor asks her to get his screwdriver which he assumes rolled under the door, it is however on top of a table on the other side of the room. Hearing this the Doctor shouts at her to get out, she again ignores him and picks up his sonic screwdriver from the table and a snake like alien then appears behind her, she eventually escapes and gives the Doctor his screwdriver which is malfunctioning as he struggles with the screwdriver he tells the Policewoman to leave as she has backup on the way, she then tells him she was lying and is actually a kissogram.

The door to the room then opens and a man and a dog emerges and the man starts barking. It then emerges that the alien is getting its form from one of the coma patients. As the Doctor tries to convince the alien not to kill them, the Guard Aliens voice from the crack is heard stating that the human residence is surrounded and that it will vacate the human residence or the human residence will be incinerated. As the alien moves to another room the Doctor gets the screwdriver to work and unlocks his handcuffs he and the kissogram then escape.

The Doctor then tries to get into the TARDIS but cant as it is still repairing itself. He then notices that the shed he destroyed has been replaced and the new shed is 12 years old. After a brief argument with the kissogram he discovers she is infact Amelia and is now calling herself Amy.

As the Doctor and Amy walk through the village they discover that the alien warning message is being transmitted everywhere in every language. The Doctor works out that the Guard Aliens will incinerate the Earth in about 20 minutes time. The aliens then put a shield around the Earth causing the sun to appear strange and lots of people to use their videophones to record it, except for Rory whose recording the disguised alien.

Rory and Amy know each other and Rory recognised the Doctor from Amy’s stories. An alien ship then appears above the village and the Doctor tries to get its attention with his sonic screwdriver, unfortunately the screwdriver burns out before he can get the ships attention. The Alien then escapes down a drain and emerges at the hospital.

The Doctor works out he needs a laptop which another friend of Amy Jeff has, and then sends Rory and Amy to the hospital to clear the ward of coma patients. The Doctor then gets to Jeff and uses his laptop to hack into an emergency conference call which is going on. He then gets the experts to send a computer virus which will act to reset every counter on the world.

At the hospital Rory and Amy are contacted by the Doctor who has commandeered a fire truck and bump into prisoner Zero who has acquired a new disguise. Amelia and Rory appear to be trapped but the Doctor then arrives and gets to them using the ladder on the firetruck.

The Doctor then confronts the alien who proceeds to taunt the Doctor as the Doctor thinks it opened the crack in the universe when it did not. The alien then tells the Doctor that the Universe is cracked, the Pandorica will open and silence will fall. This doesn’t phase the Doctor as his plan has started to work and the alien ships will be able to track the source of the virus which is the phone he is carrying which has photos of all the forms it has taken.

The alien then responds by forming a new link to Amy and the alien then takes the form of the Doctor and the young Amelia. The Doctot then works out that the alien is taking this form as Amy is dreaming of the Doctor and can still hear him. The Doctor then tells Amy to dream of what she saw in the room, this causes the Alien to impersonate itself allowing the Guard Aliens to capture it, before it is captured though it tells the Doctor that silence will fall.

While the immediate crisis is averted the Doctor is angry with the Guard aliens and uses the Shadow Proclamation to order them back. The Doctor then heads to the roof but used the opportunity to get changed into less “raggedy” clothes. On the roof the alien scan the Doctor and ask him if the world is important. The Doctor then asks them if the world a threat to them and if they are guilty of crimes by their law. He finally asks them is the world protected and what happened to previous threats to the world.

The aliens then show a montage of previous incarnations of the Doctor and flee when he tells them to run, after they leave the Doctor finds the TARDIS key is glowing and runs off and leaves in it as it is now fixed as Rory and Amy watch on.

Sometime later at night Amy hears the TARDIS arriving and runs out in her night clothes. The Doctor then asks Amy to accompany him, but she responds by telling him 2 years have passed and is reluctant. He responds by clicking his fingers to open the TARDIS which she enters and is amazed by. Amy then asks him if he can get her back by tomorrow morning, which he assure her she can.

Amy then starts to get into the spirit of things but before she agrees asks him why her, which he responds by saying that because he is lonely, Amy then agrees to go and they set off. As they depart we see that she has a wedding dress in her wardrobe and she has run off on the night before her wedding.