The VALIS Trilogy is a First Mariner Books omnibus edition published in 2011 by Houghton Mifflin Harcourt (eISBN 978-0-547-86773-1), collecting Philip K. Dick's three final novels: VALIS (1981), The Divine Invasion (1982), and The Transmigration of Timothy Archer (1982).
VALIS, originally published by Bantam, draws on Edward Hussey's The Pre-Socratics and Lao Tzu's Tao Te Ching (translated by D.C. Lau), reflecting its deep engagement with ancient philosophy. The novel is Dick's most directly autobiographical work, featuring a protagonist named Horselover Fat (a translation of Philip Dick's name into Greek and German) who experiences divine revelation and struggles to interpret mystical visions.
The Divine Invasion continues the theological exploration with a science fiction narrative about the return of God to Earth, while The Transmigration of Timothy Archer, Dick's final completed novel, takes a more realistic literary approach to questions of faith, death, and transcendence through the story of an Episcopal bishop. Together the three novels represent Dick's most sustained engagement with theology, Gnosticism, and the nature of divine reality, drawing heavily on his 1974 mystical experiences and Exegesis writings. The trilogy stands as one of the most philosophically ambitious achievements in science fiction.