In a seemingly futuristic world, the Doctor wakes up in the Big Brother house during an eviction, Rose wakes up on the Weakest Link with the Anne-Droid, and Captain Jack gets a make over with Trin-E and Zu-Zana. But something unusual is happening, and the losing contestants are being disintergrated. Obviously, it's time for the Doctor to investigate. Who or what is behind this?
After chasing an unexplained capsule through time, the TARDIS lands in London, during an air raid. Rose investigates when a small child wearing a gasmask, standing on a rooftop, continuously calls out for his mummy. After floating above the city on a barrage balloon, Rose is swept off her feet by another time traveller – Captain Jack Harkness. Meanwhile, The Doctor follows a teenaged girl to a meeting of the homeless children of the Blitz. Here, the child in the gasmask is terrorising them with a parade of strange events, constantly asking for his mother.
Rose requests a trip back to the day her father, Pete Tyler, died. Reluctantly, the Doctor agrees, but he realises he has made a mistake, when Rose saves Pete from being run over by a car. This has now changed the timeline, and Reapers are transposing themselves all over the Universe. However, this time, the Doctor doesn't have a plan…
The Doctor takes Rose on her first voyage through time: to the year five billion, when the Sun is about to expand and swallow the Earth. She is cautious and soon starts to question her reasons for joining The Doctor. But amongst the powerful alien races gathering to watch on Platform One, a murderer is at work. Who is controlling the mysterious and deadly metal spiders?