I watched this a long time ago and remember thinking it was great. On second viewing I think that the film is merely good and I gave it more credit than I should have the first time round because I was expecting nothing from a low budget Ethan Hawke movie.

The direction, action, cinematography is all pretty pedestrian and what you would expect from a low budget movie. The main draw here is the plot (based on a Heinlein short story) which is definitely interesting and worth paying attention to, even if it does force some very unlikely situations to make the logic puzzle fit. I found the ending to be a little disappointing in the way it played out (the only original part of the story) because I think it could have been done a lot more convincingly given what the character is set up to do after the end of the film.