Them

The Doctor has retired to 1892 London. Despite the protests of his allies, he is determined to keep out of mankind's affairs. However, a governess named Clara has stumbled upon a plot which only the Doctor can unravel, involving the death of her predecessor in ice and the sinister Dr. Simeon, who controls monsters made of sentient snow. And there is another mystery afoot: Clara is the spitting image of Oswin Oswald, whom the Doctor saw die in the Dalek asylum...

After a mysterious blackout, a son goes out to investigate and captures footage of actual aliens. When the aliens follow he and his brothers back to their home all hell breaks lose.

A meeting in a London bus with jewel thief Lady Christina takes a turn for the worse for the Doctor when the bus takes a detour to a desert-like planet, where the deadly Swarm awaits.

The newly-regenerated Doctor arrives in Victorian London, and Clara Oswald struggles to embrace the man he has become. All the while, they reunite with the Paternoster Gang to investigate a series of combustions that have been occurring all around the city.

After a battle with Dr. Animo in a power plant, Ben notices something strange is happening with the Omnitrix but doesn't tell anyone. Tetrax arrives and tells them the Omnitrix is broadcasting a self-destruct signal. Tetrax and Ben go to find the creator of the Omnitrix to fix it before it destroys itself and the universe along with it. Gwen stows away to help her cousin.