This inventive, side-splitting comedy was first presented by the Milwaukee Repertory Theatre, then produced in Great Britain, then went on to Broadway. The action centers on the hilarious dilemma of a young architect who is visited by a man he’s never met but who saved his life in Vietnam—the visitor turning out to be an incredibly inept, hopelessly stupid “nerd” who outstays his welcome with a vengeance.

Atlantic Stage 79th Avenue Theatre, 900 79th Ave. N. Dates and times vary. $17.50–$27.50. (877) 287-8587, www.atlanticstage.com