"When Tommy and Mai head to Paris on vacation, they are invited to a party in the catacombs under the streets of the historic city. It’s illegal yet irresistible for the young couple on the adventure of their lives. There’s only one problem. The party is a front for something far more sinister, targeting the ghosts of Paris, the street youth society has abandoned.
When Archaeology Professor James Acton and his wife discover their friends have disappeared, they leap into action, calling in all their favors to discover what happened before it’s too late, and they’re lost into a dark underworld. An underworld that has claimed tens of millions of innocents."