Trillian (character) present in work The Hitchhiker's Guide to the Galaxy
Biography
Tricia McMillan is a mathematician and astrophysicist whom Arthur Dent attempted to talk to at a party in Islington. She and Arthur next meet six months later on the spaceship Heart of Gold, shortly after the Earth has been destroyed to make way for a hyperspace bypass. The trilogy later reveals that Trillian eventually left the party with Zaphod Beeblebrox, who, according to the Quintessential Phase, is directly responsible for her nickname.
In the radio series, she is carried off and forcibly married to the President of the Algolian Chapter of the Galactic Rotary Club and consequently does not appear in the second radio series at all.  The later radio series (the Tertiary Phase and beyond) reveal this (probably) occurred only in the artificial universe within the Guide offices.  In the books, which the third, fourth and fifth series follow, she saves the universe from the Krikketeers and later becomes a Sub-Etha Radio reporter under the name Trillian Astra.
Some drafts of the movie's screenplay, and Robbie Stamp's "making of" book covering the movie, state that Trillian was to be revealed as half-human, an acknowledged divergence from Douglas Adams' original storyline. This would have been done in order to underline the loneliness of Arthur Dent, the only 100% Homo sapiens remaining in the universe, after Earth's demolition. This idea was scrapped after the "making of" book was written, and the scene revealing Trillian's heritage (by the mice, to Arthur, on the Earth Mark II) was re-written. An interview with actress Zooey Deschanel, included on the DVD version, has her mention that Trillian is half-human, suggesting the interview was recorded prior to the change of plan.Appearances
Trillian comes closest of all female characters to appearing in the entire "Hitchhiker's" saga.Novels
The Hitchhiker's Guide to the Galaxy
The Restaurant at the End of the Universe
Life, the Universe and Everything
So Long, and Thanks for All the Fish (mentioned only)
Mostly Harmless (also alternate Tricia McMillan)
And Another Thing... (also Alternate Tricia McMillan)Radio
The Hitchhiker's Guide to the Galaxy radio series
Featuring Susan Sheridan as Trillian:Quintessential Phase: "Fit the Twenty-Fourth", "Fit the Twenty-Fifth", "Fit the Twenty-Sixth"Featuring Sandra Dickinson as Trillian and Tricia McMillan:LP
Featuring Cindy Oswin as TrillianThe Hitchhiker's Guide to the Galaxy
The Restaurant at the End of the UniverseComputer game
The Hitchhiker's Guide to the GalaxyThe Hitchhiker's Guide to the Galaxy
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