It may be a B-movie, but it does get intriguing at times, with quality bits of dialog here and there. My favorite moment is when the smart gal explains to the cop the complexity of the calculation he tries to force her to perform. Solid piece of performance there.
The worst thing about the movie is the unexplained transformation into villainy by one of the characters. Feels silly and desperate, as if the writers were concerned the whole premise is not exciting enough, which it is.