Andrew Howard is Nick West, a man with a troubled past and hazy memory about to be released from the mental institution he was committed to years before after being found drenched with the blood of his missing girlfriend, ranting about demons and a chair that can span dimensions. West is confused and troubled, he hates that he cannot remember clearly what actually happened, that the memories of demons torturing his girl persist after years of treatment and the sure knowledge that this simply cannot be what actually happened. He does not believe that he has been cured, is not certain that he is safe, but his release is being forced upon him by Dr. Willard. Why would a physician insist on such a thing? Simple greed, of course. West is the sort of patient that makes careers, the ultimate test subject, and Willard has made his release conditional on two points. First, West is to be released into his direct and sole care. Second, West must accompany him back to the scene of the original crime so that his responses can be recorded and used in Willard's upcoming book.

This is, of course, a horribly bad idea.

Mason and Boyes drew international attention with Broken - the duo co-directed on that one, Mason directs solo here with Boyes as his screen writer - a film that features some of the most potent use of physical prosthetics in recent years. It's a technical astounding picture, particularly when you consider the extreme low budget it was made on, albeit one let down slightly by weaknesses in the script. Armed with better budget, better script and better cast here, the pair have reached an entirely higher level. They take a scenario that could easily have devolved into bad camp and ratchet the tension up so high it at times becomes unbearable. The script pops and crackles with smart dialogue and sharp editing, employing heavy narration in the early going - a risky move that fails more often than it succeeds but succeeds admirably here - to paint West as a deeply flawed but nevertheless likable character. The film does virtually everything well but there are three areas that lift it well above the pack.

First, there is the tone of the thing. The Devil's Chair has a restless quality to it, it simply refuses to play straight in any one direction. That would let you off the hook, you see. If they gave you stable footing you would know what to expect. Yes, this is a hard film but rather than play as a straight endurance test Mason and Boyes keep adding subtle variations to the theme. There are the shifts between the real and the supernatural, the sane and the mad. There are nods to the convention of the genre - most going to the evil doctor - that will bring a smile to the face of fans without ever slipping into parody. And then there are the jolts of pitch black comedy brought to the mix by Matt Berry, a cult UK comedian the creators fought for and wisely so. There is arguably nobody in the world better than Berry at bringing in humor without breaking the horror and he is fantastic here. And then when the time goes to go for the jugular they go for it hard. There are many forces at work here and that Mason and Boyes manage to weave them all into a coherent whole is remarkable.

Second, there is the blood. This film is not for the squeamish. It goes for it and it goes for it hard. It is bruising and punishing and made all the more so because the characters ring so true and because its creators know exactly what to leave to the imagination and what to put front and center to guarantee maximum effect.

Finally, and most importantly, there is Andrew Howard. This is his film from start to finish. It places an enormous number of demands upon him, requires far more range than is typical, and Howard is truly exceptional. The bullish, bullet headed actor will draw more than one comparison to Jason Statham - there is enough of a similarity there that he was cast as Statham's brother in Guy Ritchie's Revolver - but while Statham gets by largely on his natural charisma Howard can actually act. His performance is strong, broad reaching and entirely believable. If he were to make even the slightest mis-step the entire thing would come crashing down but instead he turns in what could easily be a star-making performance.