A Voyage to Arcturus is a novel by Scottish writer David Lindsay. It combines fantasy, philosophy, and science fiction in an exploration of the nature of good and evil and their relationship with existence.

An interstellar voyage is the framework for a narrative of a journey through fantastic landscapes. The story is set at Tormance, an imaginary planet orbiting Arcturus, which, in the novel (but not in reality) is a double star system, consisting of stars Branchspell and Alppain. The lands through which the characters travel represent philosophical systems or states of mind, through which the main character, Maskull, passes on his search for the meaning of life.

Maskull, a man longing for adventures, accepts an invitation from Krag, an acquaintance of his friend Nightspore, to travel to Tormance after a seance. The three set off in a crystal ship from an abandoned observatory in Scotland but Maskull awakens to find himself alone on Tormance.