The Doctor (Matt Smith) is on a farewell tour one day before his death. He stops to visit his friend Craig (James Corden) who is living with his girlfriend Sophie (Daisy Haggard) in Colchester and raising their baby Alfie. Craig, babysitting while Sophie is away for the weekend, figures the Doctor is investigating aliens. Just before leaving, the Doctor sees a strange electrical disturbance and decides to investigate.

The Doctor takes a job at the department store, where there are reports of employees going missing. The Doctor and Craig enter a lift and are teleported to a Cyberman spacecraft. The Doctor reverses the teleporter and disables it. With Craig’s help, he sneaks into the store at night and catches a Cybermat, which is stealing power. There is also a malfunctioning Cyberman in the basement. The Doctor reprograms the Cybermat to track down the Cybermen.

The Doctor leaves to follow the trail and Craig follows him with Baby Alfie. It seems the spacecraft is beneath the store with access from a changing room. Soon the Cybermen will have enough power to convert the human race. Craig leaves Alfie with a nice lady at the store and follows the Doctor. He is captured and put in a conversion machine to become the new leader of the Cybermen. Hearing Alfie’s cries, Craig fights the conversion and reverses it. The rest of the Cybermen painfully pick up on Craig’s emotions and overload. The Doctor and Craig take Alfie and escape with the teleporter as the ship explodes.

In the far future, River Song (Alex Kingston), now Doctor of Archaeology, notes the date and location of the Doctor’s death. She is interrupted by Madame Kovarian (Frances Barber) and agents of the Silence. River is informed that she will kill the Doctor. They put her in an astronaut’s suit and submerse her in Lake Silencio.

The Doctor has gotten blue envelopes and a Stetson from Craig’s flat to summon his friends to Utah, so he can die there. Amy has become a celebrity, appearing in an ad for Petrichor Perfume “For the girl who’s tired of waiting.” The episode got favorable reviews for Matt Smith’s and James Corden’s comedy duo and poorer reviews for the Cybermen. The Baby was played by seven babies and two dolls. The Doctor speaks Baby. Daisy Haggard was barely in the show as she was in a play at the time. The Baby Alfie would rather be called Stormageddon, Dark Lord of All. His first word is Doctor. The episode was melancholy, hilarious, and a little bit scary,