A wrinkle in time.
(Book)

Meg Murry and her friends become involved with unearthly strangers and a search for Meg's father, who has disappeared while engaged in secret work for the government. It was a dark and stormy night Meg Murry, her small brother Charles Wallace, and her mother had come down to the kitchen for a midnight snack when they were upset by the arrival of a most disturbing stranger. "Wild nights are my glory," the unearthly stranger told them. "I just got caught in a downdraft and blown off course. Let me sit down for a moment, and then I'll be on my way. Speaking of ways, by the way, there is such a thing as a tesseract." A tesseract (in case the reader doesn't know) is a wrinkle in time. To tell more would rob the reader of the enjoyment of Miss L'Engle's unusual book.