 The play which the film is based on is done in three acts; act one  is the final dress rehearsal; act two is the matinee performance;  act three is the evening performance. The bridge scenes, with  Michael Caine (I) (qv)s voiceover narration, including the  opening scene where he leaves the theatre and the ending scene where  he returns, were written for the film and do not appear in the play.  In the play, the last line is the frantic call for "Curtain!"