The Unbreakable Code

Emily and James uncover a mystery surrounding their teacher, Mr. Quisling, who seems to be receiving encrypted messages through Mark Twain books. As they decode these messages, they suspect he may be searching for a hidden treasure linked to their family's financial struggles. However, their investigation reveals connections to a historical arsonist known as The Lightkeeper and a series of fires that coincide with Mr. Quisling's activities. As they delve deeper, Emily and James find themselves entangled in a dangerous game where much more is at stake than just treasure.