List of companion characters in Doctor Who spin-offs

This is a list of fictional characters who were companions of the Doctor, in various spin-off media based on the long-running British science fiction television series, Doctor Who.

Alex is the Doctor's great grandson (the son of Susan Campbell) and features in the Eighth Doctor adventures. He is portrayed by Jake McGann.

He is initially wary of the Doctor due to the xenophobic atmosphere on Earth following the Dalek occupation. Despite this, he eventually accepts the Doctor but while he is impressed by the technology of the TARDIS he chooses not to travel with him as he wants to become an architect.

During the second Dalek invasion in the plays Lucie Miller and To The Death, Alex becomes a leader for the human resistance on Earth. He sacrifices himself to allow Lucie and Susan the opportunity to thwart the Dalek's plan.

Amy, portrayed by Ciara Janson, is a companion of the Fifth Doctor in the Key 2 Time series, which includes the plays The Judgement of Isskar, The Destroyer of Delights and The Chaos Pool.

She is a human "tracer", a device designed to track down the segments of the Key to Time across the universe. When the Doctor meets Amy, she is just a few seconds old and recruits the Doctor as her companion to find the Key.

At the end of The Chaos Pool, Romana invites Amy to live on Gallifrey and enroll in their Academy.

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