An official tie-in to the hit video game Mass Effect: Andromeda, written by award-winning and New York Times bestselling author Catherynne M. ValenteThe Quarian ark Keelah Si'yah sails toward the Andromeda galaxy, carrying 20,000 colonists from sundry races including the drell, the elcor, and the batarians. Thirty years from their destination, a routine check reveals drell lying dead in their pods, and a deadly pathogen on board. Soon, the disease is jumping species, and it quickly becomes clear that this is no accident. It's murder, and the perpetrator is still on board.The ship's systems rapidly degrade, and panic spreads among the colonists, for the virus yields a terrible swelling of the brain that causes madness, hallucinations, and dreadful violence. If the ship's crew can't restore their technology and find a cure, the Keelah Si'yah will never make it to the Nexus.

Catherynne M. Valente is the New York Times bestselling author of more than two dozen works of fantasy, science fiction, short fiction, and poetry, including Palimpsest, the Orphan's Tales series, Deathless, and Radiance. She's the winner of the Andre Norton, Tiptree, Sturgeon, Prix Imaginales, Eugie Foster Memorial, Lambda, Locus, and Hugo awards, and a finalist for the Nebula and World Fantasy Awards. She lives off the coast of Maine.