The book focuses on Artemis's partnership with the fairy, Holly Short, and their collaboration with a group of fairies known as the LEPrecon. They are trying to stop the "Eternity Code" from falling into the wrong hands.
There's no mention of Dr. Constance Lane in the book. She's a character from the *Artemis Fowl* movie, not the book series.
Perhaps you are thinking of a different character or a different book altogether?