Something weird happens: Meg feels the world around her being extinguished like a television screen being turned off, and suddenly she's alone in nothingness, unable to move or speak.
The sense of Meg's body being present begins to return to her, but she's still trapped in nothingness.
She hears Charles Wallace's voice and soon sees him, but he doesn't see her, and she still can't move or speak.
Calvin turns up too, pushing his way into reality like pushing through a curtain, but he can't see Meg either.
Meg feels like someone shoves her, and she breaks forth into this new reality.
She looks around a sees a field on a beautiful spring day, even though it's autumn at home.
Mrs. Whatsit and Mrs. Who join them, caught up in a fit of giggles. The reason for their laughter becomes clear when Mrs. Which shimmers into existence – she's wearing a stereotypical Halloween witch costume (with body to match).
Charles Wallace is less amused, on Meg's behalf, and tries to get them to explain to Meg what's going on (it seems he already knows something about it).
Mrs. Whatsit tells them that they're on a different planet and that they got there by tessering.
Calvin says that that's impossible, but Meg trusts Mrs. Which.
Mrs. Which tells Mrs. Whatsit to explain, since she's younger and therefore better at "thee llanguage of worrds" (4.50).
Mrs. Whatsit explains that it is indeed something to do with the Murry children's father, but that he's not the only reason for their journey.
Mrs. Which tells Mrs. Whatsit to show them, and says that Mrs. Whatsit should change.
Mrs. Whatsit changes – into a winged creature like a centaur only prettier.
This new creature, who says they can still call her Mrs. Whatsit, invites Meg, Calvin, and Charles Wallace onto its back.
Together they take a scenic flight over the planet's gorgeous landscapes.
At one point they hear singing, and with much effort Charles Wallace and Mrs. Whatsit manage to translate the words for Calvin and Meg: it sounds like a hymn, and gives them both a feeling of intense joy.
They pause to pick some flowers and then fly upwards into the mountains.
The reason for the flowers soon becomes clear: they're so high up that the atmosphere is too thin to breath, and the flowers are the organic equivalent of oxygen masks.
They park at the top of the mountain and admire the huge, strange moon.
Then Mrs. Whatsit turns to face the other direction (taking the children, still on her back, with her), as the sun and moon set, bringing the world into darkness.
But there's something more than darkness: a shadow on the sky, a Black Thing that makes all three humans deeply uncomfortable.
Meg briefly lowers the flower and almost passes out, but fortunately collapses into the flower and revives herself.
They fly back to the field where they began and rejoin Mrs. Who and Mrs. Which.
Meg asks Mrs. Which if the Black Thing is what her father is fighting.