At their best, puzzle movies are akin to the works of David Lynch, where the enigma to be contemplated is the movie itself, all those familiar little bits of cinema put together in a way that bends your brain. One level down from that would be movies like Christopher Nolan's Memento or The Prestige, where the movie's unusual subject matter provides a unique metaphorical handle with which to contemplate its larger themes. And then there are Riddler movies, where there's an evil mastermind who behaves like the Batman villain and makes the protagonist solve puzzles just for the sake of a clever-off. This is a more troublesome kind of movie, not only because masterminds can easily be preposterous characters, but also because the filmmakers want to woo you with the pleasure of puzzles while being dramatically obligated to conclude that you can't reduce life to silly games -- in the same way that, say, cable news's tut-tut coverage of sex is so salacious. Fermat's Room is a Riddler movie -- imagine a low-tech version of Cube, or Die Hard with a Vengeance as a one-act play -- but it's a ringer. Four mathematicians gather in a remote Spanish warehouse for what they are promised will be an intellectual gathering at which they puzzle over one of math's great unanswered questions. In reality, the room is a deathtrap, and the characters can only forestall their fate by transmitting via PDA the correct answer to riddles, while at the same time trying to understand why each is there, and who might want such vengeance on them.

One of the biggest liabilities of this genre is that such a logic-driven movie becomes extra susceptible to plausibility flaws. Examples here would be the cheap irony of the penultimate death(s) or the impossibility of writing the complex, multi-step answer to the "three switches" riddle in such a way that it can be approved by an autoresponder program. But such movies are perhaps more likely to be judged zero-sum games than your average flick, so those deficiencies are redeemed by lots of little grace moments. Early on, the hotshot young mathematician impresses girls by spontaneously breaking down a random license plate number into the two prime numbers that sum to it -- but later we see that that was actually the license plate on his car, which preps us for his later perfidy. At another moment, one mathematician asks another if had gotten a clue to solve a particular puzzle, and this exchange, in the fullness of the movie, becomes revealed as particularly preening.

All in all Fermat's Room is a nifty time at the movies, and the emotional stakes of all the characters, including the villain, are refreshingly human-scaled, but the film doesn't transcend its Riddler heart. The math-friendly audience at the Orpheum Main Stage chuckled and oohed at all the right places, happy to see just their kind of thriller.