“A Wrinkle in Time,” the first in a trilogy that was later extended to include two more books, also defied the norm. Though a major crossover success with boys as well (with more than 10 million copies sold to date), the book has especially won over young girls. And it usually reaches them at a particularly pivotal moment of pre-adolescence when they are actively seeking to define themselves, their ambitions and place in the world.

“Part of what made it seem so liberating to so many girls is that it allowed those with an analytic mind and an interest in the pursuit of science to read about a subject that at the time was not perceived of as a suitable course of study for girls,” said Leonard Marcus, author of a biography of L’Engle, “Searching for Madeleine,” to be published this fall. “At the same time, at its core it’s about a girl’s love for her father, and that emotional level transcends the genre aspect of the book.”

“A Wrinkle in Time” follows three children as they cross the barriers of time and space via something called a tesseract. On a “dark and stormy night,” Mrs Whatsit (whose honorifics appeared, also mysteriously, without periods), a celestial being disguised as an old woman, visits Meg, her mother and her younger brother Charles Wallace. Soon Meg and Charles Wallace, a prodigy of some sort (today he might be labeled Aspergian), and Calvin O’Keefe, a high school boy, are tesseracting across the universe in search of Meg’s father. They encounter at various points Mrs Who and Mrs Which, who, along with Mrs Whatsit, are also enigmatic star creatures. But it is Meg, a girl who combines both the ordinary and the extraordinary, who overcomes the book’s villain — an evil disembodied brain called IT — with the power of a simple human emotion, love.