The play is set in a very elegant top floor London flat, belonging to Philip and Joanna Markham. Philip is a straight-laced publisher of children's books, and he shares an office with his partner, Henry Lodge, on the ground floor. Philip had reluctantly agreed to let Henry borrow his apartment for the evening to 'entertain' his latest girlfriend. At the same time Joanna Markham had been persuaded by Linda Lodge to let her borrow the apartment so she can entertain her lover. What nobody knows is that the Interior Designer who had been decorating the apartment for the past three months had decided that this was the night he and the au pair girl would try out the new round bed! Not surprisingly, chaos and confusion ensue!