Art Jeffries (Bruce Willis), a renegade FBI agent, combats ruthless federal agents to protect Simon,
a nine-year-old autistic boy who has cracked the government's new "unbreakable" code. He can read
MERCURY, the most advanced encryption code yet created, as easily as other kids read English.
This ability renders the new billion-dollar secret code vulnerable, especially if enemies of the United
States should learn of Simon's abilities and capture him. Program Chief Nick Kudrow (Alec Baldwin)
orders the "security threat" eliminated, but hasn't counted on Jeffries' involvement. For reasons stemming
from a personal attachment to the boy as well as a need to maintain his own sense of humanity, Jeffries is
determined to save Simon, knowing full well that they are being trailed by deadly assassins and that no one
can be trusted. As time begins to run out, he discovers that their only hope for survival is using Simon's
special ability to bring their adversaries to justice.