In an attempt to prolong the period of time when the human body dies and the brain is still viable for resuscitation, a team of medical researchers, led by Frank (Mark Duplass) and his fiancee Zoe (Olivia Wilde) have created a serum that they believe can actually revive a recently dead brain. After many many years and failure after failure, they succeed and reanimate a dead dog. Shortly thereafter, Frank is called into the Dean's office and told he violated the terms of the grant contract. As a result of the violation, all of their work is owned by the company that provided the grant. They no longer retain any intellectual rights to the serum, the research, any of it. Seeing all his hard work stolen from him is more than Frank can handle, so he convinces the group to break into the lab and recreate and document the experiment, so they can prove that they were actually responsible. Something goes wrong, of course, and Zoe dies. Frank can't handle it, of course, and brings her back to life, of course. But, something isn't right with Zoe when she wakes up, because of course.
While the premise is marginally interesting, albeit at its core a little cliché, the film just doesn't really do much with it. Tension is key in horror movies, and all the tension in this film comes from flickering lights and “BOO!” moments. Nothing was built organically through the story; the movie tells us, “Hey, I'm being scary now--look at the flickering lights and jump cuts!” and we're supposed to just react accordingly. It's kind of like a haunted house attraction. A walk through one of those haunts is only a few minutes, so they have to just hit you hard with the obvious visual stuff. Scary masks, low light, cramped spaces, and monsters doing the old jack-in-the-box and shouting “A-BLOOGY-WOOGY-WOOO!”
There just isn't the time to build up tension in those few minutes. And sure, we know a monster is going to jump out and yell at us, we just don't know when and how, and that is enough tension in the context. A film, however, has quite a bit of time to slowly build that tension, and give us a much better pay off, something The Lazarus Effect has no interest in doing.
The film introduces ideas and plot threads, explores them for a couple minutes, then just drops them and moves on. Possible spoilery things ahead, so if you're really excited about this movie probably stop here. Before they reanimate the dog, it had really bad cataracts. After it comes back, boom, cataracts gone. The characters make a “well, that's weird” statement then never address it again. The dog itself is being intensely strange and creepy, at one point standing on the bed and just staring at a sleeping Zoe, and at another exploding the refrigerator. So, "what happens to the dog," you ask? No idea. I think it was killed off screen, but I'm not sure. The serum causes extreme brain activity in both Zoe and the dog, and maybe that is causing the all the weird stuff. But Zoe says she was in hell for years in the moments when she was gone, so did she bring back something evil with her and maybe that is causing all the weird stuff?
Throughout the film there is a science versus religion question about what happens when we die and all that, which never resolves. Maybe it's the serum, maybe it's the DMT released by the brain at death interacting with the serum, maybe it's demons and hell is real or maybe Zoe is just evil and terrible all on her own, augmented by the serum.
I am not expecting a horror film to settle the science versus religion debate once and for all, but I expect to explore the questions a little further than introducing them and immediately dropping them for strobe light effects and spooky contacts. I envision the filmmakers being asked to answer the question if it was all science or was it religion and demons, and they just answer “Yep! NNNEEOOOOOWWW” and speed away on a scooter.