After causing a botched exorcism that resulted in the death of a fellow priest and a pregnant woman, Father John Barrow (Devon Sawa) is committed to a Catholic mental asylum. Chaplain Henry Davies (Peter MacNeill) informs him that the Vatican has revoked his status as a priest. Meanwhile, Molly Hartley (Sarah Lind), the morning after celebrating both her twenty-fourth birthday and becoming the youngest partner in her firm, is arrested after police inspecting her home after a noise complaint finds the corpses of the two friends she engaged in a threesome with the night before. While interrogating Molly, she hears strange noises before she begins to have a deeper voice and refers to herself as "we". She is sent to the same mental asylum for psychiatric evaluation under Dr. Laurie Hawthorn (Gina Holden), but her condition worsens after an insect-like creature enters her body.