In 1990, as the U.S.S. Alabama passed through the Bermuda Triangle, it was struck by a mysterious energy wave, then destroyed by what appeared to be a futuristic submarine. Commander Alan Deakins was the only survivor. Years later, Dr. Lance McCarty, who studies the paranormal, wants the Pentagon to test whether there is a portal through time beneath the Bermuda Triangle. Commander Deakins, his assistant Marjorie, Dr. McCarty and a Special Forces team set out for the Atlantic. They discover and pass through the portal, emerging in the year 2077 where the Earth is in the throes of nuclear war. America is now headed by aged dictator Braddock. Deakins' grandson, John Deakins, is the leader of the rebel forces. Deakins and company escape 2077 and return to their own time to stop Braddock. They are pursued by Braddock's supporters who are determined that Deakins' grandson John will never be born.