The relationships that poet Philip Larkin had with Monica Jones and Maeve Brennan were well-known. However analysis of some of his poems led fellow poet Andrew Motion to believe that Larkin had a relationship with another woman, and after keeping the secret for many years, his secretary Betty Mackereth confirmed in 2010 that she was "the third woman". In this documentary, Betty talks about Philip's complicated love-life and his overlapping relationships with her, Monica and Maeve, and about several previously of Philip's previously unpublished poems which he wrote to her.