If your soul is sent to Hell by mistake, you had better hope your loved ones can afford a Soul Retriever. These men and women who brave the depths and horrors of the underworld to rescue the unfortunate spirits who have been incorrectly relocated there are not easy to come by, but it’s the only way to bring a pure soul to its rightful place in Heaven. Getter is one such Soul Retriever, and on top of his day-to-day grind against demons, wormholes, golems, and worse, he happens to be the subject of a certain prophecy which may bring balance to Heaven, Hell, and All of Creation.

This time, Getter is sent down to the realm of Satan to retrieve the soul of a man called Matthew Ainsley on what is supposed to be a relatively mundane expedition. Unfortunately for Getter, it becomes rapidly more complicated than he expects, and he’s forced to team up with a few others to finish the job. Gregory, the 150-year-old soul of a Scotsman who has helped him out in the past, escorts Getter to the Sanctuary to meet up with his on-again, off-again partner Sneaker. Sneaker isn’t one to meddle with: her skills are among the best in the business, but she rarely receives the acclaim she deserves from the other mostly-male Soul Retrievers. On top of all that, she’s recently been turned into a vampire, and isn’t terribly pleased with the ordeal.

Together, the trio discovers that things aren’t all hunky dory downstairs in the underworld - there are many who believe Satan has lost his edge and fallen out of touch with the reality of Hell, and there are those who would see him deposed as ruler. Mephisto, the Chief of Helland Security, is one such schemer. In order for the status quo to be maintained, the Council of Soul Retrievers decides to take action. When someone even more evil than Satan wants to take over Hell, and doesn't care about disrupting the balance of the universe, there's only one thing to do - Warn The Devil. But will that warning be enough? Will Satan even take heed of this warning from a Soul Retriever?

This exciting supernatural adventure is the sequel to Soul Retrievers. Another vivid romp through the diverse landscape of Hell, Warn The Devil’s unlikely heroes join forces to keep the balance of evil - for good of humanity.