I was somewhat impressed with 'Deliver Us from Evil' because it's the sort of movie they don't make any more in Hollywood. I doubt it'll do well at the box office and it probably won't make many waves, but it's likely to resurface down the road in lists of films you ought to see but probably haven't heard of.

The picture's biggest problem lies in perception. The title is painfully generic and hints at a horror movie, which it really isn't, at least not in the form that viewers generally expect nowadays. There are a couple of minor jump scares but they're weak and not important to the big picture. Scott Derrickson, who directed and co-wrote, has a background in horror and this could easily be seen alongside other films of his like 'Sinister' and 'The Exorcism of Emily Rose', but each of those are notable different.

This is far more of a drama that starts out as a crime thriller or police procedural and gradually moves into horror territory, not only with the theme of demonic possession but through a sustained creepiness that outdoes anything I've seen in many years. Unfortunately, the audience who might appreciate that most isn't likely to be the one who watches the movie.

It's inspired by a non-fiction work, 'Beware the Night', by New York City cop Ralph Sarchie (and his co-writer, Lisa Collier Cool) who retired from the force to investigate the paranormal, assisting in exorcisms and fighting ancient evil. Sarchie is the lead character here, in the form of Eric Bana, perhaps best in serious films like 'Chopper', 'Black Hawk Down' or 'Munich' but most recognised in blockbusters like 'Hulk', 'Troy' and the reboot of 'Star Trek'. He does good work here, as a strong but imperfect cop who reconnects with his religious roots to move forward when he must.

Unsurprisingly Sarchie is shown as competent throughout. Attending a violent dispute early in the film, he finds that the offender is a US marine who doesn't want to go easily. Yet he and his partner, capably played by Joel McHale, have the upper hand throughout and take him in somewhat effortlessly. That's one way to show that your leads are tough from the outset.

And they need to remain very much so, because the crimes they attend, to which Sarchie is often driven by a sixth sense he calls his 'radar', are not commonplace ones. A woman throws her two year old into the lion enclosure at the Bronx Zoo; she's found scrabbling at dirt and reciting the lyrics to 'Break On Through' by the Doors. A family believe their house is haunted and, on searching the basement, a corpse falls out of the wall not far away from a crucified cat.

Gradually the connections begin to reveal themselves, because all these cases are connected: doors, painters, crucifixes, strange odours and Marines. The heart of it seems to revolve around a trio of the latter who we see in the opening scene. They're in a cave in Iraq, where their tech fails and in the ensuing darkness something appears to take them.

The mystery unfolds well, but it's not rocket science to figure out where it's going, because enough connections arrive early to shape our expectations. Derrickson keeps a tension in play throughout, gradually tightening it but rarely pandering to those who want shock moments. It's unusually sustained, because most films would break it in down scenes, through comic relief or domestic downtime, but this one doesn't. Sarchie doesn't have a troubled home life but he can't unwind and so only spreads the tension to others who aren't involved in his work life.

More than anything, it maintains a creepy tone through the use of lighting. The film starts dark and stays dark, for almost its entire running time. Scenes either take place at night or in dim lighting, which deteriorates to no lighting at all because power outages are common in the locations they get to visit. Even the uniforms are dark: not just those of the cops but that of Fr Mendoza too, a Spanish priest who appears briefly early on but is inextricably woven into the story. His presence grows with the film until the point he dominates.

The darkness isn't just a choice of lighting, it has meaning. The story is a fight between the forces of light and the forces of darkness and for the majority of the film, the latter are clearly winning. The first scene shot in daylight is a flashback to before the paranormal entered Sarchie's life. Even then it's not a nice, pleasant memory, but it's a reminder of the reality that he knew before the darkness took over. The second daylight scene comes when Fr Mendoza convinces Sarchie, who describes himself as 'a lapsed Catholic', that he needs to turn back to God and he decides to seek absolution.

It's this sort of thing that will hold the film up to posterity. There's little here that horror fans haven't seen before, often many times before, in possession movies. It clearly owes a great debt to 'The Exorcist' but it can't take too many liberties with its source material because Sarchie claims that it's all true. So it's not going to be remembered for its story. It'll mostly be remembered for its abiding tone of dread, its refusal to break us away from that even for a moment and its solid adherence to the slow build. Those aren't values modern audiences tend to care about, but cinephiles in future years will.

Bana is strong, as he tends to be, in the lead; he's one of the most underrated actors that people have heard of. Sean Harris is a wonder as Santino, the possessed third Marine, as different as could be imagined from the last role I saw him in, as Ian Curtis in '24 Hour Party People'.

My discovery here though was Édgar Ramírez, the Venezuelan actor who plays Fr Mendoza. He's played major parts in a number of blockbusters of late, 'The Bourne Ultimatum', 'Wrath of the Titans' and 'Zero Dark Thirty', but I haven't seen any of them. When I do, it'll be tough not to recall him here, as an unlikely and very worldly Jesuit. 'You ain't no saint, Father,' Sarchie tells him. 'I'll give you that.' He has the sexy, unkempt look of David Krumholtz, but with a Latin accent, a mature outlook and a charisma to him that will carry him far.

If you want to catch this in the theatre, you may need to do so quickly, even though it's a July release. It's likely to vanish without any acclaim but pick up something of a fanbase in years to come from reevaluations and a gradual connection to the right audience. It is what it is and that isn't what most will expect.