When Tom's brother becomes ill, Tom is sent away to stay with his aunt and Uncle. To his great dismay, he finds that they live in a block of flats without a garden. Then, one night he cannot sleep, and thinks he hears the old grandfather clock in the entrance hall strike thirteen. He creeps down to check - but when he reaches the hall, he finds that there is a huge and beautiful garden behind the flats that he wasn't told about. But there is something peculiar about it; for a start, the people he sees there are all dressed in Victorian costume - and no-one, except for a little girl called Hattie, seems to be able to see him.
Are Hattie and the others all ghosts? Or is Tom a ghost himself, visiting a real world? Or is he time-travelling back through time when the clock strikes thirteen? Tom becomes obsessed with his midnight garden, wanting to spend more and more time in it - but with every visit Hattie grows a little older. Time is running out.
An intriguing tale; mysterious, atmospheric - and enchantingly written. The ending is genuinely moving. The modern-day segments of the story seem a little dated now, but in a time-slip story this really doesn't matter. A classic book that has stood the test of time - a true childhood favourite.