Setting off again in their beloved Airstream trailer, Joe and Dottie Loudermilk head to Washington, D.C., where their errant son involves them in all manner of political skulduggery. Visiting Washington, D.C., has been one of Joe Loudermilk's lifelong ambitions, so it's a natural stop on his and his wife Dottie's never-ending road trip across America known as retirement. Unfortunately, Dottie never mentioned to Joe they'd be meeting their son Eddie for dinner. As the family's political extremist, he doesn't exactly see eye to eye with Joe; where Eddie sees a government conspiracy around every corner, Joe simply sees his tax dollars at work, so no one is surprised when they start in with their arguing almost immediately upon arrival. As usual, it's Dottie who ends up referee, somehow managing to sweet-talk both husband and son into submission. All is calm - but not for long. An ex-compatriot of Eddie's crashes the party, gun in hand, accusing Eddie of stealing his girlfriend. When the fellow later turns up dead, Eddie is charged with murder, and Joe and Dottie find their vacation has become a race with the devil to clear their son's name.