A doctor was a character in William Shakespeare's play Macbeth. (PROSE: The Empire of Glass)
In earlier drafts of the play, this doctor's role was instead fulfilled by a character named the Doctor who was based upon the Second Doctor. (PROSE: The True Tragedie of Macbeth) For the first staging of Macbeth, performed in the presence of King James I and Queen Anne, the Doctor was played by the First Doctor though this casting had not been authorised by the King's Men. At the end of Act IV, the Doctor and his companion Vicki Pallister clambered onto the stage in order to get Shakespeare, who was himself playing Lady Macbeth, to take an amnesia pill. The actor who was on the stage at the time hissed at them to get off but the Doctor claimed to be a friend of the King and threatened that he would be "most displeased" if he was not allowed to participate in the production. The actor exited rapidly through the curtain and, although there was some commotion backstage, the play was allowed to continue with the Doctor and Vicki assuming the roles of Lady Macbeth's doctor and the gentlewoman respectively.
Appearing in Act V Scene I, the Doctor first asked the gentlewoman about the last time Lady Macbeth walked in her sleep. He then asked her what Lady Macbeth had said during these episodes but the gentlewoman closed this avenue of questioning by replying "nothing I can report". Lady Macbeth then entered with a light. The Doctor wondered how she had obtained the light and observed that her eyes were open, the gentlewoman adding "but there's nobody home". During the original performance, the Doctor had helped Vicki with her lines through cues and gestures and was also attempting to discretely persuade Shakespeare to take the amensia pill during the scene. It was at around this point that the explosion of a Jamarian space shuttle distracted Shakespeare and the audience enough for the Doctor to force-feed him the pill. As the Doctor summarised, King James was "slightly annoyed at the abrupt curtailment of the play but the free firework display outside the Palace mollified him somewhat" while Shakespeare had forgotten the events of the last few days and was confined to bed for a short time. (PROSE: The Empire of Glass)
The Fourth Doctor later recalled to Sarah Jane Smith that he had portrayed the Doctor alongside Shakespeare when Macbeth opened at the Globe Theatre. (PROSE: Managra)