Paycheck is (another film) based on a on a Philip K. Dick short story. The story (or at least the central idea behind the story) is strong: it follows an engineer (played by Ben Affleck) who works on secret projects and after he has completed the work he has his memory wiped. He takes a job which involves a phone number pay check and a couple of lost years. When he returns to the 'real' world he finds himself in great danger with only a set of seemingly innocuous items he has mailed himself for protection.
This first half hour is strong and well handled, in particular the scenes that involve the engineer being placed in jeopardy and extricating himself with seemingly useless items are very well done. However, after the strong start the film loses its way. Once the conspiracy is revealed it simply heads for the conclusion at breakneck speed via a series of action set-pieces. In my opinion, the best Philip K. Dick adaptations (e.g. Blade Runner) explore the themes of book but Paycheck simply falls back on a set of well-handled but ultimately formulaic action sequences. Quite enjoyable in a rather mindless way but much of it is unbelievable (a ninja engineer and a kung-fu botanist?!?) and a number of inconsistencies to creep in which detract from the film.
Another problem is that rhe casting never quite works: Ben Affleck is OK but playing an amnesiac leads to inevitable and unfavourable comparisons with Matt Damon in the Bourne films. Uma Thurman, who plays the botanist love interest, can be excellent but this is not one of her better performances, she seems oddly disinterested and often appears to be just going through the motions. The supporting cast are all competent but none are outstanding.
I enjoyed the movie, but after the first half an hour I had to switch my brain off. The real disappointment is that it could have been so much better.