Trix MacMillan

Trix
Doctor Who character
First appearance	Time Zero
Last appearance	The Gallifrey Chronicles
Portrayed by	None
Information
Affiliated	Eighth Doctor
Species	Human
Home planet	Earth
Home era	21st century

Beatrix MacMillan, or simply Trix, is a fictional character in the Eighth Doctor Adventures novels based upon the British science fiction television series, Doctor Who. The Eighth Doctor first met her in Time Zero, but it was not until Timeless that she went on to become one of his companions.

Trix's name may be a reference to Tricia McMillan, a character in The Hitchhiker's Guide to the Galaxy, by Douglas Adams, who was a script editor on Doctor Who and wrote a number of stories for the series.

The details of Trix's life before becoming involved with the Doctor have never been made clear, but it seems likely that she was a con artist, possibly involved in sex work at some point. In The Gallifrey Chronicles, she at one point evades arrest by police, who know her by the name "Patricia Joanne Pullman" and are seeking her for the murder of Anthony Charles Macmillan (suggesting that the name she uses while travelling in the TARDIS is an alias).

When she first met the Doctor, she was posing as a descendant of Tsar Nicholas II, a role that the Doctor's then-nemesis Sabbath hired her to play. At the end of the novel, she stowed away in the TARDIS, making brief appearances in some subsequent stories but managing to avoid detection by the Doctor and his companions until Timeless.

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