Julie Christie stars in this screen adaptation of the classic novel by L.P. Hartley. A young teenage boy, Leo, is invited to a wealthy school friend's rich family estate & is drawn into a love affair between his friend's twenty-something sister, Marian, & the family neighbour, even though she is engaged to be married. She uses Leo as a go-between, sending messages to her lover. Despite feeling he is betraying her fiance Hugh, Leo carries on being the messager boy & discovers more about the attraction between men & women along the way.