Professor's fob watch, similar to the one which changed the Doctor from a Time Lord into a human. She rushes to tell the Doctor about the watch as the Professor hears voices coming from it. The Doctor initiates the launch sequence of the rocket at the same time that the Professor opens the fob watch. A frantic Doctor runs back to the control room, but the Professor lets the Futurekind inside the silo. Chantho confronts the Professor. He responds that his name is the Master. Chantho and the Master both fatally injure each other. The Master leaves in the TARDIS, with the hand inside, and regenerates into a younger form. The Doctor, Jack, and Martha are stranded. Continuity The episode marks the return of the Master, who last appeared during the 1996 television movie Doctor Who. Derek Jacobi plays the fifth version of the Master whom the Doctor has encountered on screen, and John Simm is the sixth. At least one television pundit speculated whether "Mister Saxon" was an intentional anagram of "Master No. Six" or was perhaps "a big red herring". However, when asked, Russell T Davies stated that it was not deliberate. Production This episode was announced as the first of a three-part story in Totally Doctor Who, broadcast the day before. Prior to this, only the following two instalments had been linked. Later reference material, including Doctor Who Magazine'''s season poll, treated the three episodes as a single three-part story. Russell T Davies has said that he regards "Utopia" as a separate story, but notes that the determination is arbitrary. This is the first episode in the revived series to credit three principal cast members within the title sequence, with the addition of John Barrowman, who plays Captain Jack Harkness. Casting This is Derek Jacobi's third involvement in Doctor Who. The first was in the September 2003 audio drama Deadline, where he played a screenwriter who believes himself to be the Doctor. The second was several months later, in the webcast Scream of the Shalka, where he played an android version of the Master. In 2017, Jacobi reprised his role from "Utopia" in the audio drama series The War Master. Other actors returning to the franchise in this episode are Neil Reidman had previously played Tom Braudy in the Eighth Doctor audio drama Memory Lane and Robert Forknall, who plays Lord Byron in the Eighth Doctor audio