Gnosia

Saddled with amnesia, Yuuri awakens on an interstellar cruiser drifting through space. Unfortunately, a lack of memories is the least of Yuuri's problems. Among the four other crew members is a Gnosia: a Gnos infectee whose goal is the eradication of humanity. The Gnosia appears human in all other respects, so the uninfected have little choice but to vote on whom they suspect to be the enemy, hoping to neutralize the Gnosia by putting them into cold sleep. If the Gnosia survives the vote, they will eliminate one crew member during the cruiser's following warp, when only the Gnosia remains conscious.