In 1857 Abner Marsh, owner of the failing Fevre River Packet Company, is contacted by Joshua York, who offers to fund the construction of a new steamship, the Fevre Dream. Marsh accepts and allows York to join him as co-captain. However, York and his associates are never seen in daylight hours, leading to talk among the suspicious crew. York claims to Marsh that he and his friends are vampire hunters but it is revealed that they are vampires, albeit ones with a noble intention: to cure their fellow vampires of their thirst for blood via a special potion.