In New Orleans, Ben Matthias, an astrophysicist developing a camera to detect dark matter, marries Alyssa, a tour guide for the city's famously haunted places. Alyssa dies in a car crash, and a despondent Ben gives up his career and continues to run her tour, despite his disbelief in the supernatural. Widowed doctor Gabbie and her son Travis move into the abandoned Gracey Manor, which they hope to turn into a bed and breakfast, only to discover the mansion is infested with ghosts.