In the heart of the catacombs, evil stirs. Sarah Pearson is lured into the eerie depths of the Paris Catacombs after seeing an unsettling video. On it, the ghostly appearance of an old friend beckons her into the darkness. But the Catacombs hold more secrets than Sarah anticipates, and the shadows within are not all from the dead. Sarah's friends—David Ritter and Reverend Rachel Quinn—find out about her perilous journey and move to stop her. Racing against time, they must find and rescue their friend from the grip of the underworld. In doing so, they are confronted with chilling legends of restless souls and malevolent entities that have waited centuries for the likes of Sarah to venture into their realm. As Sarah becomes further entrenched in the maze below, a perilous game of cat and mouse ensues. For David and Rachel, time is of the essence, because if Sarah is possessed by the entities lurking beneath Paris, then the whole world will teeter on the brink of the apocalypse. Catacombs is Book 8 in the Haunted series.