Adam Mitchell (Doctor Who) old. He quickly forms a mutual attraction with the Doctor's companion Rose Tyler (Billie Piper) and informs her of his desire to see the stars. When a live Dalek manages to break free and slaughter its way through the base, Adam finds himself fleeing along with Rose. At the end of the episode, when van Statten's museum is closed down, Rose asks the Doctor (Christopher Eccleston) to take Adam along with them in the TARDIS. The Doctor is reluctant, but Rose convinces him to let Adam follow them into the TARDIS. In the following episode, "The Long Game", the Doctor,
Doctor Who Doctor's nature, somewhere between the twelfth and final incarnation. On rare occasions, other actors have stood in for the lead. In "The Five Doctors", Richard Hurndall played the First Doctor due to William Hartnell's death in 1975; 34 years later David Bradley similarly replaced Hartnell in "Twice Upon a Time". In "Time and the Rani", Sylvester McCoy briefly played the Sixth Doctor during the regeneration sequence, carrying on as the Seventh. For more information, see the list of actors who have played the Doctor. In other media, the Doctor has been played by various other actors, including Peter Cushing in