What Happens while Margot is in the closet?

The sun comes out for one hour, the hour that Margot is locked in the closet.

They surged about her, caught her up and bore her, protesting, and then pleading, and then crying, back into a tunnel, a room, a closet, where they slammed and locked the door.

Ray Bradbury's short story is set in the future, when people live on Venus. There it rains constantly; the sun only emerges once every seven years. Since the children are nine years old, they have no memory of the sun. Because she has moved to Venus from Earth, only Margot remembers what the sun looks like and how it feels warm on the flesh and "like a blushing" on the face, and how it looks "like a penny." She stands apart from the others and does not wish to play their games with them in the underground tunnels of the city, which are artificially lighted. It is because she does not play with the others and because she never sings unless the song is about the sun that the other children hate her for "these reasons of big and little consequence."
When one cruel boy sees in Margot's eyes that she eagerly waits for the hour of the sun, he tells her "It's all a joke!" but she insists that this day is the one which the scientists have determined that the sun will emerge.

"All a joke!" said the boy, and seized her roughly. "Hey, everyone, let’s put her in a closet before the teacher comes!" "No," said Margot, falling back.

The cruel children push Margot into a closet, watching as she throws herself against the door desperately. They smile as they turn and go back down into the tunnel before the teacher arrives. When the sun does come out, the children are ecstatic; they squint at the sun, and they remove their jackets to feel the rays upon their arms.

They put their hands up to that yellowness and that amazing blueness and they breathed of the fresh, fresh air and listened and listened to the silence which suspended them in a blessed sea of no sound and no motion.

And then it is over. A raindrop falls in one girl's hand. Then, another girl utters a faint cry: "Margot." Margot, whose greatest desire was to again see and feel the sun, has been in the closet all the time that the sun was out.