Lizzie is burdened by the secret of Ethan's past, but should she tell him? While Lizzie struggles with her moral dilemma, the rest of the gang get excited at a huge opportunity - the Headmaster is leaving the school premises to tour the schools he intends to hoodwink into joining the Hazelbrook Academy chain. With the Headmaster away, the gang will play - but how?

The gang decide to find out where the Headmaster came from and stumble on an intriguing clue that sends Lizzie, Ethan and Angelika on an exciting adventure. Following the clue leads them to an abandoned school, and they set off on a scary treasure trail around the building. Is whoever set this trying to help them, or is it a trap?

The gang get excited that they're not alone - someone else knows about the Headmaster! They hope that rescue is on its way, but their search for whoever left the message is fruitless - until a mystery teacher with attitude shows up. Who is she?