It's a stormy night, and Meg is huddled in her attic bedroom, freaking out.
Part of the reason for her fear isn't the storm – it's her sense of being a permanent outcast, doomed never to fit in with her classmates at school.
Meg goes downstairs to make some cocoa and finds her little brother Charles Wallace already on cocoa duty.
Meg thinks about Charles: how he too doesn't fit in, how he's smarter than most people give him credit for, and how he seems to read Meg and her mother's minds.
Meg and Charles are joined in the kitchen by Mrs. Murry.
Mrs. Murry tries to comfort Meg that things will get better for her.
Meg waits in fear while her mother goes to check out what their dog is so upset about.
Meg makes a sandwich for their visitor, Mrs. Whatsit, despite not trusting her.
Meg sees her mother get upset by Mrs. Whatsit's parting remark about a tesseract.
Meg wakes up the next morning hoping it was all a dream. Meg's mother tells her it really did happen, but puts off explaining what a tesseract is.
Meg goes to school, nearly falls asleep in class, and mouths off at her teacher.
Meg is called to the principal's office, and mouths off at him too.
Meg comes home and finds Charles Wallace there alone.
The two of them take Fortinbras (their dog) on a walk to visit the cabin where Mrs. Whatsit lives with two friends.
Meg is comforted by Charles's obvious affection for her.
Meg and Charles run into Calvin O'Keefe, a boy who goes to Meg's school.
Charles Wallace asks Meg about Calvin, but she's not able to tell him much: Calvin's in the popular crowd while she's not.
They enter the cabin, Calvin taking Meg's arm to comfort her as it's said to be haunted, and they meet Mrs. Who.
Meg, Charles Wallace, and Calvin go to the Murry house for dinner.
Meg is glad that she and Calvin are going to be friends.
Meg tells Calvin about her missing father.
Meg helps Calvin with his math homework, despite his being a few grades ahead of her.
After dinner, Meg talks with her mother about how Charles Wallace is different from everyone else.
Meg and Calvin go for a walk in the garden, and talk some more about Meg's missing father.
Meg and Calvin are interrupted at a tender moment by Charles Wallace, who is followed by Mrs. Whatsit, Mrs. Who, and Mrs. Which. Way to kill the mood, guys.
Meg suddenly disappears into nothingness, and then slowly finds herself again.
She sees Charles Wallace and then Calvin, but they seem unable to see her, and she can't call out to them.
She finally manages to break through to where they are, which turns out to be a field on another planet.
Meg wants to go find her father right away, and is impatient when they tell her she has to wait.
Mrs. Whatsit changes into a winged centaur and takes the three children for a trip on her back to see something.
They pass some other winged centaur creatures who are singing, and Meg wants to know what the words mean.
Mrs. Whatsit, with Charles, manages to provide a rough translation, and Meg feels filled with joy.
They pick up some oxygen-providing flowers to help them breathe at the high altitude they're headed for.
Meg briefly forgets to use her oxygen flower, and nearly passes out for a moment.
Meg looks at the Black Thing and thinks that Charles Wallace shouldn't be seeing this.
Meg asks Mrs. Which if the Black Thing is what her father is fighting, and starts crying when the answer is yes.
Meg is comforted by Mrs. Whatsit.
Meg still doesn't understand the tesseract, so Mrs. Whatsit and Charles Wallace try to explain, and she almost gets it.
Meg again dissolves into nothingness as they tesser to their next destination, but feels squashed flat when Mrs. Which tries to land them on a two-dimensional planet.
Meg is worried that her mother is worried about them, but Mrs. Whatsit assures her that if all goes well she'll never even know they were gone.
Meg looks into the Happy Medium's crystal ball and sees the Earth shadowed by the Black Thing.
Meg is scared, and Mrs. Which comforts her by saying they will keep fighting.
Mrs. Whatsit insists that Meg add to the list started by Calvin and Charles Wallace of the All-Star Earthling Darkness Fight Squad; she comes up with a few names, but is more concerned with when they're going to get around to saving her father.
In the crystal ball Meg sees a star give up its life to fight the Black Thing, and realizes that the Mrs. Ws made the same sacrifice.
The Happy Medium offers them some food, and Meg realizes that she is hungry, but Mrs. Whatsit refuses for her before Meg has a chance to accept.
The Happy Medium offers to show them their mother before they go; Meg would rather see her father, but accepts the offer, and asks that Calvin be allowed to see his mother as well.
Meg is angry to see her mother sad at home, and thanks the Happy Medium for making her less scared.
Meg kisses the Happy Medium goodbye.
Again they tesser, and this time Meg has a sense of coldness as they pass through the Black Thing.
On Camazotz, Meg receives gifts from the Mrs. Ws: her faults, Mrs. Who's glasses, and a comment to go down into the town.
Meg goes with Charles Wallace and Calvin towards the town, and is impatient when they want to stop and ask people questions.
Meg doesn't want to go into the CENTRAL Central Intelligence Building, but the two boys override her.
Meg holds hands with her companions as they enter the building.
Meg and the others encounter the man with the red eyes.
Meg screams "Father!" and the man stops reciting the multiplication table.
Meg asks the man to tell them where her father is.
Meg pulls Charles Wallace back when he attacks the man with the red eyes.
Meg tackles Charles Wallace when he gets hypnotized by the man, bringing him back to himself.
Meg crankily tells the man that she's hungry, and he obliges with a (fake) turkey dinner.
Meg is suspicious, but eats.
Against Meg's wishes, Charles Wallace lets himself be hypnotized by the man again.
Meg is distraught to see Charles Wallace replaced by a soulless automaton.
Meg grabs onto Chucky (the weird, hypnotized version of Charles Wallace), but he pulls her off.
Meg calls for Mrs. Whatsit, with no response.
Meg and Calvin follow Chucky, who says he's taking them to Mr. Murry.
Meg tells Calvin to use his Mrs.-Whatsit-enhanced gift of communication on Chucky, and it almost works.
Meg debates Chucky on the merits of forced conformity.
Meg sees her father and runs toward him, but can't get into the room he's in.
Meg pleads with Chucky to let her in, but he's too much of a soulless jerk to oblige.
Meg puts on Mrs. Who's glasses, which allow her into the room with her father.
Meg is relieved to have finally found her father.
Meg tries to explain to her father what's going on with Charles Wallace and everything else, but thinks he doesn't understand.
Meg gives Mrs. Who's glasses to her father so he can see.
Mr. Murry leaves Meg in the column where he was imprisoned, then comes back to get her.
Meg is disappointed that not only is her father is not able to make everything instantly better, but he doesn't even seem to understand the extent to which things are wrong.
Meg follows the others to IT.
When Meg enters IT's chamber, she has to catch her breath as her heart and lungs are forced into IT's rhythm.
Meg is horrified that IT is a giant disembodied brain.
Meg tries to resist IT by reciting the opening of the Declaration of Independence, which leads her to the revelation that being alike and being equal are not the same thing.
Meg's father tries to help her by getting her to recite the periodic table of elements, and then square roots, but she is fading fast.
Meg's father grabs her and she passes out as they tesser away.
Meg slowly wakes up; she hears the voices of her father and Calvin, but is unable to speak or even move.
Meg finally manages to talk, but still feels mostly frozen.
Meg is in despair that her father left Charles Wallace behind in the power of IT.
The beasts arrive and carry Meg off; at first she is horrified by their eyeless faces, but feels comforted by their touch.
Meg at first tries to resist the beasts, but eventually relaxes and falls asleep, and feels much better when she wakes up.
Meg talks with the particular beast who has been taking care of her, who asks her to call her Aunt Beast.
Meg joins her father and Calvin for breakfast, but gives them the cold shoulder because she's still angry about Charles.
Meg tries to explain Mrs. Whatsit to the beasts, but fails.
Meg is filled with hope as the Mrs. Ws suddenly appear.
Meg is impatient that the Mrs. Ws aren't instantly making things better, and that they won't let Mr. Murry or Calvin return to Camazotz to save Charles.
Meg realizes that she is the only one that can save Charles, and is upset at first, but then resigned.
Meg makes it up with her father and Calvin (who kisses her) before she goes.
Meg receives gifts from the Mrs. Ws: Mrs. Whatsit gives her love, Mrs. Who gives her a speech, and Mrs. Which gives her the knowledge that she has something IT has not.
Meg returns to Camazotz, and walks through the empty streets to the building where IT is, trying to figure out what she should do.
Meg arrives in IT's chamber and finds Chucky still there.
Meg talks with Chucky and realizes the thing she has that IT doesn't: love.
Meg stands there and focuses on loving Charles Wallace, and he is released from IT.
Meg and Charles are tessered back to Earth.
Meg and Charles find themselves in the garden at home with Mr. Murry and Calvin, where they are soon joined by the rest of their family.
Meg is joyful when the Mrs. Ws briefly turn up, but they soon disappear again.