While Minty Kane's mother hovers in the misty time of a coma after an automobile accident, Minty encounters two abused children from past centuries and struggles to help them find peace. Recently widowed, Kate Kane has brought her daughter to vacation with Aunt Mary while Kate works at her new job. Minty is aware of her own sensitivity--to the cold place on the back stairs betokening some old sorrow, the icy tongues that make her spine shiver. So she's not really surprised when the sundial/moondial in the old National Trust garden near Aunt Mary's house takes her to past time--19th-century suntime, and a consumptive potboy, Tom, who longs to be reunited with his little sister; 18th-century moontime and tiny, sweet-singing Sarah, who's tormented as the devil's child because she bears a birthmark. Meeting Tom in her world and his, Minty soon understands his situation. Sarah is more elusive, but Tom and Minty together face down her tormentors on a long-ago Halloween and show Sarah her own pretty face, for the first time, in a mirror that does not shatter; Tom and Sarah depart together in peace. Meanwhile, Minty has recounted these mysterious events to her mother, via cassette; her loving voice helps to bring Kate back from moontime. Carefully wrought and evanescent as a ghost story should be, this will be enjoyed by any admirer of Tom's Midnight Garden, the Green Knowe stories, or A Chance Child Like those fine fantasies, Moondial is grounded in crucial emotional reality, deepened and strengthened by the imaginative elements of the story.