Wife goes to private eye to investigate her husband, who is conducting odd experiments in his family's remote cabin. Investigations reveal an eldritch intrusion of the past into the present. . .
Low-budget (and very Canadian, eh) but well done adaptation of H.P. Lovecraft's The Case of Charles Dexter Ward, that manages to stick pretty close to the novel. The acting is somewhat variable, but Sarandon is fine, and once the film picks up and goes into what Ward and his ancestor were actually up to, the film becomes very good indeed.
Poorly marketed and obviously tinkered with by the studio, it ended up direct to video. It does have asutained and mounting sense of dread, which helps contribute to its modest cult status. It is probably the most faithful adaptation of the generally unfilmable Lovecraft's works (other than art and student films) to this day.