Tim returns to school, but he is behaving strangely. Discovery of the tunnel puts the Unlisted in jeopardy, and the twins have to decide whether they can trust their Bua when she accepts a job with the GCI.

Cast: Vrund Rao, Ved Rao, Abigail Adriano, Miah Madden, Jean Hinchliffe, Nya Cofie, Saba Zaidi Abdi, Nicholas Brown, Virginie Laverdure, Avishma Lohith, Zenia Starr, Otis Dhanji, Suzi Dougherty, Aria Ferris, Annabel Wolfe