Alcock (Singer to the Sea God, 1993, etc.) leavens this fantasy with generous doses of her usual sly wit, raising it a cut above other time-travel tales. There's always been something odd about Mary Frewin, from the time she was in her pram. She sees ghosts--sometimes just a foot here, a shoulder there--and, among the full-bodied ones, they all have flaming red ears. No one believes Mary, not even her long-suffering parents. Her teacher's new boyfriend, who's interested in the paranormal, discovers that Mary's great-great-grandmother, Mary Coram, who disappeared long before the girl's birth, shared Mary's gift; in fact, she's not seeing ghosts at all but creatures from Izel, a parallel world plagued by timequakes that render space and time utterly chaotic. Mary Coram disappeared there, and Mary Frewin believes she must follow in her ancestor's footsteps. This clever story is full of unexpected developments and lively, unusual characters, including the Bad-Dog Boys, a gang of louts who torment Mary in the real world, and a motley crew of Izellians in the other. Grand fun.