After the events in Coldbay where they sealed the hell hole Lucy is trying to learn more about it and how to save Murzzzz from eternal damnation. Yes he's a demon but he's also a part of the family. Lucy's turned to her diocese for guidance but they've gone strangely quiet so she persuades the Rooks to drive there so they can sort this out. On the way they realise something is incredibly wrong with a motorway service station - it's empty except for lingering sad ghosts and. . . oh no another hell hole has opened and sucked in a load of people. They know they need to rescue them and close it down but not before they've done everything in their collective power to rescue Murzzzz. After all one man's hellhole is a family of ghost-hunter's opportunity to save their demon friend.
