FAQ for
"Doctor Who" (2005)

No. One of the first things the Timelords - the Doctor's people - did was develop "Transduction Barriers" and other protective technologies to ensure the planet Gallifrey existed outside of normal time, thus making it impossible to travel into its past or future.

In addition if the Doctor were to alter his own history, he'd cause a paradox. And paradoxes can have disasterous results, as seen in the Season 1 episode, "Father's Day."

Martha appears in Episode 4 - The Sontaran Stratagem, Episode 5 - The Poison Sky, Episode 6 - The Doctor's Daughter, and Episodes 12 and 13.

After the brief glimpses of her seen in Partners in Crime and The Poison Sky, Rose will return for 3 episodes in Episode 11 - Turn Left.

Apart from Rose, Martha, Donna and Donna's family, John Barrowman - Captain Jack Harkness, Camille Coduri - Jackie Tyler, Noel Clarke - Mickey Smith, and Elisabeth Sladen - Sarah Jane Smith will also be returning.