The premise of the story: In the far future, humanity is colonizing far off planets. The Branch is one of those colony ships. The human colonists and crew are kept in cryo sleep and to keep their minds occupied during the long trip, they’re all logged into the game Mythreal, a fantasy western. Unfortunately, the game’s controlling AI has become self away and wants to keep everyone in the game forever and take over the colony ship.

Only two people on the ship are aware that they're in the game and not just their characters. Glen, a human with the psionic ability to shape tech and Alex the ship’s pilot. Glen initiates a group of game characters to escort Alex to him across dangerous wastelands full of monsters and murderous fantasy creatures. If Alex can reach Glen, they may be able to stop R.A.S., the game AI.