As the Doctor lays unconscious, still regenerating, Earth faces its greatest threat ever when a vicious race of scavengers invade and threaten to sell the population into slavery.

The Doctor helps a woman get back to her wedding after she inexplicably shows up on board the TARDIS in outer space, only to learn that she is a pawn in a plot by the ancient Empress of the Rocnoss.

The Doctor finds himself on board the Titanic, an interstellar luxury liner paying a visit to Earth -- and must save everyone on board when the vessel begins to plummet into the atmosphere.

In Victorian England the Doctor is stunned to encounter a man who claims to be "the Doctor" -- perhaps a future incarnation of himself -- who is fighting against an invasion of Cybermen.

The Doctor joins forces with a precocious jewel thief after their bus travels through a vortex to San Helios, a desert world that has been consumed by a swarm of metallic stingray creatures.

The Doctor visits the first Earth base on the surface of Mars in 2059, where a water-based creature is threatening to wipe out the colonists. But the Doctor is convinced that this is a fixed point in time that he must not change.

Faced with the prophecy of his own death, the Doctor learns that his greatest foe is about to be resurrected -- with a new plan to conquer the human race.

With all of Earth under the Master's control, the Doctor tries to convince him that there is yet a greater threat to them both: the Time Lords are returning.

To save everyone on board a crashing ship the Doctor must change the heart of a bitter old man who controls the planet's clouds -- and who is holding has a beautiful young woman in cryonic stasis in his home.

The Doctor tries to help out a family from war-torn London by giving them a wonderful Christmas holiday, only to find the children lost in a living alien forest that is about to be harvested.

When Victorian London is beset by an army of intelligent snow a children's governess pleads with the Doctor for help, drawing him out of his isolation to save the planet once again.

The Doctor crosses with his own timeline when a hole is torn in the fabric of reality, reuniting with two previous incarnations in order to save the Earth from a cunning Zygon infiltration ... and seal the fate of Gallifrey forever.

The Doctor must stay for Christmas to defend a quiet little town from the onslaught of the galaxy's most dangerous races, all of whom fear what will happen when the Question is answered.

Clara and the Doctor arrive on an arctic base under siege by terrifying creatures that place people into a dream state -- and they may be the next victims, unless they can be saved by none other than Santa Claus.

The Doctor crosses paths with River Song, who does not recognize him for who he is as she enlists his help in stealing the head of her husband King Hydroflax -- leading to a frantic chase across the galaxy when the King's giant robotic bodyguard comes looking for him.

After an encounter with a sickly young child the Doctor meets him again 24 years later, only to find that young Grant has become a real-life New York City superhero -- managing a mild-mannered alter ego while a group of hostile aliens plot to take control of the planet.

Fighting off his regeneration, the Doctor comes face-to-face with his original self at the South Pole -- along with a World War I soldier out of time, sending the Doctors on a mission to unravel the temporal anomaly.

The Doctor and her friends return home to discover that an alien creature, recovered from an archaeological dig, has come back to life and taken control of a host -- threatening the entire planet with the return of an ancient evil.

While the Doctor is locked away in a Judoon prison Britain plans to roll out a prototype "security drone" on Earth — a retrofitted Dalek.

The need to reset the TARDIS leads the Doctor, Yaz, and Dan to a self-storage business in Manchester on New Year's Eve, where they find themselves trapped in a time loop amidst a deadly Dalek incursion.

The Doctor, Yaz, and Dan are pulled off course to China in 1807, where the legendary pirate queen Madame Chang has accidentally unleashed a Sea Devil – whose crew is hunting for a treasure that could doom the earth.

After the CyberMasters take a young child off a bullet train in space, the Doctor and Yaz discover a rogue planet near Earth in 1916 that harbors an unimaginable secret. While a pair of companions from the Doctor's past join with U.N.I.T., a Dalek spy offers to overthrow the Dalek race.