Gattaca is set in the not-too-distant future.  Genetic modification has developed to such an extent that parents are now able to order custom babies, eliminating what would have been any physical liabilities and putting in their place brains, brawn and beauty (the movie derives its name from the letters found in DNA sequences: G, A, T and C).  This technological advance has created a two-tiered society of elites (called "Valids") and normal people (called "In-Valids").  The former get the best jobs and all the perks, while the latter muddle along as best they can.  The protagonist, Vincent, was born the normal way, but he refuses to settle for mediocrity.  He aspires to be in space.  And nothing is going to stop him.