Tom, arriving at his aunt and uncle's flat in an old manor house, is intrigued by a clock in the downstairs hall that often strikes the wrong time. When he hears it striking 13 at midnight, he feels he must go down in the dead of night to investigate... and gets the surprise of his life.
Tom's friendship with Hatty continues, though not all those in the garden are as friendly to Tom... at least, not those who can see him.
Hatty, older at each of Tom's successive visits now feels too old to play with him as she used to, leaving Tom lonely and depressed. As his time in the garden draws to a close, Tom is surprised to learn that a piece of the garden remains with him still in the present day.