Sister, Sister

Lucy Bonnard helps run the Willows with her sister Charlotte on their Louisiana bayou plantation. Lucy's fragile mental state colors daily life at the inn. Etienne LeViolette, a childhood friend who now works as a handyman, is pressing his attentions on Lucy. Charlotte, meanwhile, is having a romance with Sheriff Cleve Bonnard, who ends it blaming her devotion to Lucy.

Matt Rutledge, a congressional aide from Washington, arrives at the Willows as a guest and is quickly drawn to Lucy. His attraction complicates the dynamic among the sisters and local men. The dinner later includes Mrs. Bettleheim, her daughter Fran, and Fran's husband Lenny, who all stay at the inn.

During the storm, Lucy entertains the guests with a ghost story about Jud Nevins who disappeared years ago. She insists that other spirits in the bayou protect her from Jud's malign presence. Etienne observes Matt's growing interest in Lucy and becomes enraged by the rivalry.

The next morning, Beaux, the sisters' beloved dog, is found murdered and Lucy grows hysterical, blaming Jud's ghost. Moments later, Etienne arrives at the house and accuses Charlotte of being Jud's killer.

That night, Matt returns to the Willows and is stopped on the road by Etienne, who warns him that Charlotte is dangerous. The warning underscores the fragile loyalties among the guests and residents. The tension between Matt, Etienne, and Charlotte escalates.

Cleve Bonnard, the town sheriff, reviews Jud Nevins's missing person file at the police station and finds a photograph of Jud with a boy who resembles Matt. The discovery deepens the sense that someone close to the inn might be connected to Jud's disappearance.

Matt returns to the Willows, but Charlotte forbids him from seeing Lucy, whom she has locked in her bedroom. Lucy manages to smash a window to alert Matt, who rushes upstairs and breaks down her bedroom door. The two then have sex in Lucy's room.

During a childhood memory, Lucy recalls playing in a graveyard with Etienne when she witnessed Charlotte being assaulted by Jud. Charlotte killed Jud in a struggle, and the two disposed of his body in the bayou. When Charlotte sends Lucy back to retrieve Jud's baseball cap, Lucy glimpses a silhouette she takes to be Etienne.

Lucy spots a man wearing Jud's jacket and baseball cap outside and chases him, only to realize the silhouette belongs to Matt, not Etienne. The mystery of Jud's killer deepens as loyalties blur.

Etienne is shot with a bow and arrow in the bayou by an unseen attacker, then crawls to the front porch where the attacker confronts him. The killer is revealed to be Matt, Jud's younger brother, confirming a deeply personal motive.

Lucy returns to the house and is confronted by Matt, who implies Charlotte murdered Etienne. Charlotte explains to Lucy that Matt is manipulating her to avenge his brother's death, turning Lucy's trust against her.

Overwhelmed, Lucy flees into the bayou while Matt attempts to drown her. Hands rise from the swamp, pulling Matt under, and he is killed. A fog rolls in and the ghostly figures of several people, including Etienne, emerge before vanishing.

Some time later, Lucy helps Charlotte prepare for her wedding to Cleve at the Willows. While looking at herself in a mirror, Lucy has a vision of Matt breaking through the glass and attacking her, which she realizes is only a vision.