When Agatha and Tedros came to the School with Merlin in Book three, he puts them under the gender-switching spell used by Yuba and Tristan in book two. Agatha becomes Edgar, "resembling a malevolent penguin, with sickly pale skin, sunken cheeks, bulging eyes..." While Tedros became Essa, "broad shouldered and golden tan, with glimmering blue eyes, a small button nose, and hair so harshly black it didn't look its natural..."
They were introduced as new students by Lady Lesso's "spies," Hester, Anadil, and Dot. They said they "weren't old enough to get the first go at being Nevers." Sophie questions their joined hands, and Hester interjects and says they're cousins from Captain Hook's family tree, extending the lie.
A few hours earlier; Merlin had told them there are two tasks, one of them had to retrieve Excalibur from the School for Old, and one would get Sophie from Rafal's tow- "ME!", they shouted. Merlin questioned them about Sophie until, surprisingly, Tedros won. He knew the name of Sophie's mother, Vanessa, when he and Agatha were on Necro Ridge.