Harry Potter and the Chamber of Secrets

Throughout the summer holidays after his first year at Hogwarts School of Witchcraft and Wizardry, Harry Potter has been receiving sinister warnings from a house-elf called Dobby. Now, back at school to start his second year, Harry hears unintelligible whispers echoing through the corridors. Before long the attacks begin: students are found as if turned to stone. Dobby’s predictions seem to be coming true. Source