It was a dark and stormy night. . . .
Meg, having decided to leave her attic bedroom, discovers that the reason her little brother Charles Wallace didn't come up for her was that he was waiting in the kitchen, heating milk for her cocoa -- and her mother's. And then one Mrs. Whatsit arrives -- she's met Charles Wallace, and after being blown off-course, decided to stop by. And knows things that she has no way of knowing about their father's disappearance.
When Meg and Charles Wallace walk their dog the next day, they meet a boy from her school -- Calvin. And further meetings not only with peculiar Mrs. Whatsit, but Mrs. Who and Mrs. Which, even stranger, lead to their setting out to rescue their father -- involving that wrinkle in time.
It involves the Darkness, a planet where all the children bounce balls or skip rope, a mother who doesn't know why they are knocking on her door, strange eyeless aliens that talk through tentacles, how Mrs. Whatsit came to be what she is, a lot of quotations from Shakespeare or the Bible, and much more.