Medical researchers Frank (Mark Duplass) and his fiancée, Zoe (Olivia Wilde), have developed a serum, code-named “Lazarus”. It was intended to assist coma patients but is shown to actually be able to bring the dead back to life.
With the assistance of their friends, Niko, Clay and videographer Eva, they run a successful trial on a recently deceased dog. But the serum has unanticipated effects. The dog’s cataracts disappear, it loses its appetite, and it demonstrates other strange abilities. Tests reveal that the serum, instead of dissipating, is constructing strange new synapses within the dog’s brain.
When the dean of their university learns of their underground experiments, their project is shut down. They are also informed that a major pharmaceutical corporation has bought out the company that funded their research. The company and their attorneys confiscate everything associated with the project.
Frank and his team sneak back into their lab to duplicate the experiment so that they can prove that they created the serum. During this attempt things go horribly wrong and Zoe is electrocuted. Unwilling to let her go, Frank uses the serum to resurrect her. Initially, the procedure appears to be a success, but the team soon realizes that something is wrong with Zoe. She claims that when she died, she went to hell and begins to demonstrate unusual abilities. The Lazarus serum causes brains to “evolve” incredibly rapidly – giving Zoe powers of telekinesis and telepathy The serum also causes increased aggression with horrifying consequences. Niko walks into a room and is startled by Zoe.