The author of The Shadow on the Dial (1987) puts a new wrinkle in one of her favorite themes: time travel. At first, the reader may suppose that Garet Atkins, 13, and her ""twin"" Daisy, who suddenly arrives via the laundry chute to live with Garet and her ""grandmother,"" Gratkins, are actually different sides of the same personality--or is Daisy Garet's imaginary sister, embodying attributes she rejects for herself? Not exactly: Daisy is actually a duplicate of Gratkins, who simultaneously did and didn't fall through the chute 50 years ago--and so, she finally discovers, is Garet herself, who arrived at the age of two. All three are really Margaret--Gratkins as a child--a fact that doesn't stop them from thinking and behaving as different and separate people in the present. Garet happens to be writing her autobiography as a school assignment when these unlikely events occur. An indifferent student who's hooked on writing, she's forced into amusing subterfuges to continue her narrative while preparing an alternate version for her pompous, incredulous English teacher--just one of the subplots that enrich this clever book. Lindbergh exploits the situation's rich possibilities with considerable charm and wit, though her logic isn't rigorous and she blithely ignored questions like what became of Gratkins's eight brothers and sisters. Never mind--it's a lively and entertaining story, crammed with funny situations and on-target dialogue. Enjoy.