Yaël, Arthur and Idriss are in discovery class at the sea. On the program: a visit to the environmental research center and the underwater recycling station of Professor Mendelssohn, a scientist who has put his fortune at the service of saving the planet. But demonstrations of ecological projects turn into disaster. Yaël is convinced that this is sabotage. With Idriss and Arthur, she sets out in pursuit of the culprit.

Follow their investigation and solve the puzzles to find out who is causing the science projects to fail.

Translation by Google Translate