Jill Masters (Izabella Miko) has not seen or heard from her ex-lover, Roderick "Rick" Usher (Austin Nichols), or her best friend (Rick's twin), Madeline "Maddy" Usher (Danielle McCarthy), for three years. One night, Rick contacts Jill and informs her of Maddy's sudden death. Her last wish was for Jill to attend the funeral. Conflicted, Jill returns to the family home of the Usher family. Her love affair with Rick is rekindled as she learns he suffers from the same malady that robbed his twin sister, Maddy, of her sharp mind before taking her life. His affliction is manifested in a rare nerve condition, which renders him hypersensitive. Under the watchful eye of the caretaker, Nurse Thatcher (Beth Grant), Jill appears to be haunted by Maddy's ghost.
Meanwhile, Jill becomes intimate with Rick and tells him she has missed her period. A pregnancy test confirms Jill is pregnant. In the meantime, Jill has discovered that the Usher family has practiced twincest for the past five or six generations, right down to Maddy and Rick. All the prior generations had twins, who later became a couple and birthed twins of their own and so on down the line to Maddy and Rick, who were to continue the Usher curse.