Mission House was not built for three people. Especially when one of them won't stop humming.

When Bea Hanlon follows her preacher husband Max to a remote island in the Pacific, she soon sees that their mission will bring anything but salvation. It's not just the rats and the hordes of mosquitos and the weevils in the powdered milk. Past the confines of their stuffy little house, amidst the damp and the dust and the sweltering heat, rumours are spreading of devil-chasers who roam the island on the hunt for evil spirits. And then are the noises from the church at night. Just as Bea begins to adapt to Advent Island, the arrival of an unexpected, wildly irritating and always humming house guest rattles her new life. And before long, trapped in the jungle and in the growing fever of her husband's insanity, Bea finds herself fighting for her freedom, and for her life.