Jerry Fletcher (Mel Gibson) is a New York City cab driver who seems to have absorbed every bit of crackpot information passed along as suppressed news that's surfaced on talk radio or the Internet in the past 20 years. Anti-United Nations militia men who are actually U.N. operatives? NASA scientists engineering earthquakes?
Oliver Stone's secret life as a government agent discrediting conspiracy theorists? Jerry's heard 'em all and believes most of them, and even publishes his own journal of forbidden information, with a subscription list that now totals five people.
In short, Jerry seems like just another New York City lunatic, and while he spends a fair amount of his spare time following Alice Sutton (Julia Roberts), a government attorney, Alice regards him as harmless; he once intervened while she was being mugged, and he's been acting like her benign if whacked-out protector ever since.
However, one day Jerry is kidnapped and worked over by CIA operatives; he is convinced that one of the theories he uncovered must be for real -- but he has no idea which one. He tries to get Alice to help him, and before long both are drawn into a dangerous web that leads to a startling revelation of just how Jerry got this way.
Mel Gibson gives a fine comic performance, and those with a taste for alternative media will have fun dissecting which of the theories Jerry spouts are real (or at least appeared before this film was made) and which were the invention of the screenwriters.