A government courier is caught in a deadly cover-up after discovering that his murdered sister was not only the mistress of a U.S. president, but also a Soviet spy.

A group of people from different backgrounds have one thing in common: when they hear the world "gumball" whispered by one of the others, they know that it's time for the Gumball Rally: a no-holds barred, secret, winner-take-all rally across the USA.