The plot: A couple visit a fertility clinic, not knowing that they also do research into human cloning... and devil worship. And book publishing.
This is an outright, brazen ripoff of Rosemary's Baby, though it's also somewhat influenced by other supernatural thrillers, such as The Omen. If you've seen Rosemary's Baby, you really don't need to see this. It's got a pretty decent cast, but that's about the best I can say for it.
There were some half-decent ideas here, and I think that they could have worked in the hands of a better director. I'm not saying that they were good ideas, but a skilled exploitation director could have turned this into an enjoyable, derivative waste of time. Instead, we get a somewhat inept attempt to plagiarize one of my favorite horror movies.
Despite all its faults, it's still watchable. I can't recommend it, though.