Troy (MATTHEW McCONAUGHEY) is a successful attorney in the D.A.'s office who doesn't believe in luck and views the world in a positive light. Yet, when he's involved in a hit and run accident, his life and his view of everything changes forever. Walker (JOHN TURTURRO) is a physics instructor who's cheating on his wife, Patricia (AMY IRVING), by having an affair with Helen (BARBARA SUKOWA), a fellow teacher. Despite his repeated proclamations of cause and effect, he doesn't seem to realize he's causing his marriage to fail.
Beatrice (CLEA DuVALL) and Dorrie (TIA TEXADA) are housecleaners who have different views of life. While Dorrie is a bit pessimistic while also envious of the lifestyles of the rich and famous, Beatrice is optimistic about life and believes that wonderful things will happen. Something does, but it's not wonderful and it changes her view of life forever.
Meanwhile, Gene English (ALAN ARKIN) and Dick Lacey (FRANKIE FAISON) are managers in an insurance claims deparment who can't believe how perpetually cheerful and optimistic one of their workers, Wade Bowman (WILLIAM WISE), always is. While Gene can tolerate other employees such as Mickey Wheeler (SHAWN ELLIOT), Wade's eternal happiness drives him crazy. Accordingly, and while having to deal with his delinquent, drug addict of a young adult son, Ronnie (ALEX BURNS), Gene sets out to upset Wade's applecart of good cheer.
As he does so, the various characters' paths and lives cross, directly and indirectly influencing certain occurrences that change their views of themselves, their world and their thoughts about the balance of happiness and despair.