In Cancun, Mexico, police investigate a slaughter at a wedding ceremony. In Dublin, Ireland, the clientele of a backstreet pub are found dead. In Kyoto, Japan, the bullet train pulls into the station with blood-spattered windows. It is the time of the Black Sun. Across the world, the wolves are calling to each other. Locked in bodies that had no idea they were there, they rise from the depths of the unconscious and turn towards America . . .

For Hellboy, it's a race against time to prevent a devastating wave of primal savagery washing across the land. And so he is drawn to Boston's Beacon Hill and the Grant Mansion, believed to be the most haunted house in New England, where the truth may lie buried.