When Henrietta and Inspector Howard search for a missing German immigrant woman, their investigation leads to the infamous Dunning Hospital for the insane, where the poor disappear behind locked doors. Meanwhile, a mysterious spiritualist claims to speak with the dead. As both cases deepen and a young epileptic girl's future hangs in the balance, Henrietta must venture alone into the asylum's shadowy corridors. But Dunning holds dark secrets, and not everyone who enters emerges unchanged.