Hermione Granger is crucial to Harry and Ron in their successful mission to solve the mystery of the Chamber of Secrets. Hermione is revived after Harry kills the basilisk, but she is distraught to learn that all end-of-year exams have been cancelled as a school treat. Hermione buys a cat named Crookshanks, who takes to chasing Ron's pet rat, Scabbers. Before the start of term, Professor McGonagall secretly gives Hermione a Time-Turner, a device which enables her to go back in time and handle her heavy class schedule, though this is not revealed until the penultimate chapter. Much tension comes into play
Harry Potter (character) becomes fast friends with classmates Ron Weasley and Hermione Granger, and foils Voldemort's attempt to steal the Philosopher's Stone. He also forms a rivalry with characters Draco Malfoy, a classmate from an elitist wizarding family, and the cold, condescending Potions master, Severus Snape, Draco's mentor and the head of Slytherin House. Both feuds continue throughout the series and are settled at the series's end (Draco's in the West End play Harry Potter and the Cursed Child and Snape's on his deathbed in Harry Potter and the Deathly Hallows. In a 1999 interview, Rowling stated that Draco is based on several