Three episodes had been written before it was cancelled because of the imminent return of the live series. The Doctor is visually modelled on Grant himself. Grant has described his interpretation of the Doctor as "Sherlock Holmes in space." The Shalka Doctor has an aristocratic bearing. He is resentful of an unseen power directing his travels. He refuses, at first, to intervene in the Shalka invasion of the village of Lannet until the death of a homeless woman raises his ire, and is abrasive with the military characters who ally with him in the Shalka story. He seems haunted by some undisclosed past event, to the point where he actively opposes the notion of Alison becoming a companion. The android which contains the consciousness of the Master (voiced by Derek Jacobi) hints that the Doctor's previous companion may have met an untimely end.