Artemis was sitting in obligatory therapy with Dr Po when his eyes closed.
To Dr Po, it would appear that the young Fowl boy had simply fallen asleep, which though irritating wasn't something that really mattered so much to the therapist.
Actually what had happened was the boy had astral projected.
Artemis—or rather, his soul—was standing in the Nexus, directly in front of Kuri.
He noticed that her eyes were glowing bright white and her whole form was pulsing with magick.
Had she summoned him here with her power? Why would she call him?
After all, the two had parted as enemies in the previous escapade.
Suddenly he was alerted to her as she began to speak. Along with her words, the mist began to form pictures, and he assumed he was seeing her vision.
"Artemis Fowl II...the Nexus recognizes you..." Kuri said. "You must find the Keeper of the Nexus...find this person...and you will be granted your heart's desire..."
When she said Nexus, a collaboration of images and formulae allowed Artemis to understand what this truly was: the central core of all magic. Apparently it was kept here to prevent fairies or humans from taking it for themselves.
When Keeper of the Nexus was said, Artemis searched the Mist for a clue as to who this person was, but none was given. Only the word 'person' which made Artemis believe that they must be human.
Hearts desire. Artemis almost allowed himself to return. He had heard all he needed. But the mist formed again, and showed him his family, both parents, healthy and returned to him.
Hopelessly, Artemis reached out and traced his mist-father's face.
"I will find them."