Think Carefully before seeing this dangerous (yes, dangerous) movie
If you are considering seeing this movie, I implore you to get very grounded in scripture so that your thinking is not severely poisoned. This is not too strong a statement - please bear with me and seriously consider this critique before seeing or showing this movie to anyone.
I do think the movie was well-made, directed, acted, etc. but I was very disappointed and sorry I brought it home. There are some key reasons why.
Healing and raising the dead are, according to the commands to us in the Bible, supposed to be normal for the Christian church at large. The fact that the churches involved in the movie were so taken by them, and as well that they were totally attributed to an evil personage, is a sad but true commentary of the state of the church (and I do know that there are some who may read this that see miracles in your churches weekly - obviously not talking about you but you ARE a minority :).
The 2nd reason is that, for those Christians that are NOT aware of their authority in Christ (see Luke 9, 10, Matt 10, James 5 for examples), this movie has a high potential for making them think that anything of this nature must be of the devil. There weren't any examples of Christians correctly operating in these areas to bring any balance. That the very holy gifts that have been given us through the holy presence and ministry of the Holy Spirit were only represented as attributed to demonic activity is very close to blaspheming Him and His ministry.
Lastly, that the demons had such an upperhand over the saints (e.g. could restrain them at will) is a totally false representation of reality (again see the Luke references) and could bring extreme fear on the unlearned/immature in the truth.
Don't get me wrong, considering author Frank P.'s heart (we've read his original thrillers and his Dr. Cooper series, various articles as well as heard numerous interviews with him over the last 18 years) I'm sure these serious consequences were not his intention - indeed there are issues here he may not be aware of.