Maureen O'Hara ("Julie) and John Payne ("Bill") are a happily married, successful, theatrical couple for whom all is going well until she starts to feel a bit poorly. It transpires that she has an heart condition, so she decides that it might be a good idea to adopt a child so her husband will have someone once she has gone. She alights on the rather high maintenance "Hitty" (Connie Marshall), a girl with lots of fantastic dreams of unicorns, and whose heart is in the right place. Bill, initially, doesn't take to the youngster but as things run their inevitable course, the three of them must…