The barrier between worlds has shattered. Demons wreak havoc across Earth; the dead are rising from their graves; psychics and witches are vanishing without a trace. The fate of the world rests in the hands of the enigmatic Tresser Corporation, a company of demon soldiers? and a kindergarten teacher. In other words, humanity's odds aren't looking great. When hunter, David Tresser, pairs up with a High Demon, he knows he's in over his head. Of course, there are worse positions to be in, like Henry, whose girlfriend hasn't been seen since the demonic attacks began, or the psychic Cassandra, who has become a target of those very demons herself. As this motley crew teams up, trust is slow to be gained?but they really have no choice when the world around them is falling apart at the seams. In the midst of it all, Tresser finds himself curiously drawn to the demon he's not even sure he can trust. After an exorcism gone terribly wrong, the team is left with no choice. To save their worlds, and themselves, they'll have to travel into the darkest part of Hell: the Pits of Gehenna, from which no one has ever returned. To defeat the odds and preserve humanity, they'll all have to work together.