Meg suddenly feels herself torn apart from Charles and Calvin and thrust into silent darkness. She tries to cry out to them but finds she does not even have a body, much less a voice. Suddenly, she feels her heart beating again and sees Charles and Calvin shimmer back into material presence. Mrs. Whatsit, Mrs. Who, and Mrs. Which inform the children that they are on the planet Uriel. When Calvin inquires into their mode of travel, Mrs. Whatsit explains that they do not travel at any one speed, but rather "tesser" or "wrinkle" through space. Meg wonders if this term relates to the "tesseract" that Mrs. Whatsit mentioned earlier.
Mrs. Whatsit tells the children that the life of their father is threatened, and they are on their way to him, but first they have stopped to learn what they are up against. With Mrs. Who's permission, Mrs. Whatsit transforms herself into a beautiful creature with a horse's body and a human torso. Calvin falls to his knees in shameless devotion, but Mrs. Whatsit admonishes him for his unthinking worship of her.
The children climb on Mrs. Whatsit's back and she flies across fertile fields and a great plateau of granite-like rock. Below, beautiful creatures perform a musical dance in a garden, and Mrs. Whatsit translates their music into the words of the Biblical verses of Isaiah 42:10-12. Meg is overcome with joy and instinctively reaches out for Calvin's hand. As they travel upward through the rarefied atmosphere, Mrs. Whatsit hands them each clusters of flowers and tells them to breathe through them when the air becomes too thin.
As they travel through the clouds of Uriel, Mrs. Whatsit shows them a view of the universe not observable from Earth. The children see a great white disk that Mrs. Whatsit identifies as one of Uriel's moons, and watch a sunset and moonset. Then, above the clouds, they see a blackness that seems to envelop all the stars around it. Meg knows instinctively that the shadow is the most concentrated form of evil she has ever seen, for it is not cast by any object but is a Thing itself. When they return to the flowery fields beneath, Meg walks directly up to Mrs. Which and asks if the Dark Thing they saw is what her father is fighting.
On the planet Uriel, the children encounter both the tremendous good and the tremendous evil that are currently at battle with one another. The vision of the good, consisting of beautiful creatures engaged in musical dance, compels Meg to hold out her hand to Calvin. Through she does not yet realize it, this love she feels as she reaches out to Calvin will be her ultimate weapon in fighting off the evil forces.
This entire chapter is replete with religious allusions and connotations: the planet Uriel is named for one of the guardian angels of the Biblical tradition; and Calvin will eventually compare Mrs. Whatsit, Mrs. Who, and Mrs. Which to guardian angels who travel with and protect them on their cosmic quest. Mrs. Whatsit translates the music of Uriel's beautiful inhabitants into Biblical verses; the garden that the travelers fly over resembles Eden in its majesty and serenity, and Meg mentally describes it as "bliss." Finally, Calvin falls to his knees to worship Mrs. Whatsit when she changes her external form, and implicit in her rebuke ("never to me") is the suggestion that there is another Being more worthy of his devotion. These religious motifs reflect L'Engle's passionate commitment to developing her own Christian theology in her writing.