A group of medical researchers led by Frank and his fiancée Zoe has been working on a groundbreaking project to bring the dead back to life. Their experimental serum, codenamed "Lazarus," shows promise in reviving deceased animals, with a dog being their first successful resurrection. The team observes that the dog exhibits unusual behaviors post-resuscitation, raising concerns about the effects of the serum. Despite this, the group is excited about the potential of their discovery, fantasizing about the implications it could have on medical science and the possibility of conquering death.

Their project, however, is threatened when a pharmaceutical company learns of their breakthrough and seizes control of their research, along with all related materials. In a desperate attempt to replicate their success and reclaim their work, the team conducts an unauthorized experiment. This leads to a tragic accident that results in Zoe's death. Grief-stricken and driven by a mix of love and obsession, Frank decides to use the Lazarus serum on Zoe, attempting to bring her back to life. The experiment yields unforeseen consequences, as Zoe returns from the dead with newfound, inexplicable abilities. The team quickly realizes that meddling with the balance between life and death has perilous ramifications, as their project spirals out of control, leading them into a nightmare from which they might not escape.