Surgeon Elizabeth (Robin Weigert, TV's DEADWOOD) has relocated to a new town after the accidental death of her fiancee. She rents a remote house that was once a Civil War field hospital with its own Confederate ghost. Despite concerns from her friend Rachael (Sybil Temtchine, THE SWEETEST THING) that Elizabeth has stopped seeing her therapist and thrown out her anti-depressants, Elizabeth fills her free time by resuming her interest in painting and her work hours with an interest in comatose stabbing victim Jason (Anthony Carrigan), which causes tension between her and operating surgeon Russell (Jay O. Sanders, EDGE OF DARKNESS). When the ghostly presence of civil war soldier Elijah (Paul David Story, IN TIME) makes itself known, Elizabeth embraces the presence (who also lost the love of his life). When Jason's wife decides to have him removed from life support, Elizabeth manages to resuscitate him and transport him to her home on a newly-introduced high-tech gurney (with built-in monitors and defibrillators) where she hopes to coax Elijah's spirit into the soulless body. The result is successful and Elijah lives again in Jason's body. Elizabeth and Elijah consummate their relationship and - out of necessity - keep their relationship (and Elijah's existence) private. While Elizabeth is away at a party thrown by Rachael, Elijah goes out to a bar and gets into a fight with the boyfriend of a flirtatious girl. When the girl turns up dead the next morning and the description of the last person she was seen with matches the presumed-dead Jason, Lt. Wascoe (Wes Studi, AVATAR) starts snooping around and finds that Jason's body has become untraceable after it was signed off by Elizabeth. When Elizabeth confesses her secret to Rachael, her friend raises the concern that Jason might either be conning her or - if she were to buy the ghost story - that perhaps not all traces of Jason's murderous personality are gone from his body.

The directorial debut of Peros (who had previously adapted his own play for Peter Bogdanovich's THE CAT'S MEOW), THE UNDYING gets off to a nice start with an atmospheric location and a good lead performance from Weigert. The hauntings by the spectral form of Elijah are effective (including two jump scares that actually work). Unfortunately, once the ghost takes over a living body, the film veers into supernatural romance territory for a very long stretch. Elizabeth's attempts to acquaint Elijah with modern life are played for subtle humor (Elijah mistaking landlord Henry [Franklin Ojeda Smith, INVINCIBLE] for "the house negro" and so fascinated with television that he becomes a bit of a couch potato while Elizabeth is at work), but pacing of most of the second act is entirely too leisurely. Robert F. Smith's photography veers between atmospheric and bland (all of the sequences at Elizabeth's house are well-lit, while the exteriors and hospital scenes have a flat-looking TV look), and Christopher Caliendo's score - other than some Nathan Barr-esque strings - is more than a bit intrusive at times (particularly the see-sawing piece that underscores Elizabeth's smuggling of Jason's body out of the hospital).