and the Chamber of Secrets Hermione (along with Ron's mother Molly Weasley and a few female students of Hogwarts) develops a liking for Defence Against the Dark Arts (DADA) teacher Gilderoy Lockhart as he had written all the books required for the DADA in Chamber of Secrets. During a morning confrontation between the Gryffindor and Slytherin Quidditch teams, a brawl nearly ensues after Draco Malfoy calls her a "Mudblood", an insulting epithet for Muggle-born wizards when she defends the Gryffindor Quidditch team. She concocts the Polyjuice Potion needed for the trio to disguise themselves as Draco's housemates to collect information about the Heir of Slytherin who has reopened the Chamber of Secrets. However, she is unable to join Harry and Ron in the investigation after the hair plucked from the robes of Slytherin student Millicent Bulstrode (with whom Hermione was previously matched up during Lockhart's ill-fated Duelling Club) was that of her cat, whose appearance she takes on in her human form; it takes several weeks for the effects to completely wear off. Hermione is Petrified by the basilisk after successfully identifying the creature through library research. Though she lies incapacitated in the hospital wing, the information she has found and left behind 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. Harry Potter and the Prisoner of Azkaban Hermione buys a cat named Crookshanks, who takes to chasing Ron's pet rat, Scabbers. Before the start of term, Professor Minerva McGonagall secretly gives Hermione a Time-Turner, a device which lets her go back in time and handle her heavy class schedule, though this is not revealed until the penultimate chapter. Much tension comes into play between Hermione and her two best friends; Harry is furious with her because she told McGonagall that he got a Firebolt, which was confiscated to be inspected for traces of dark magic. Ron is angry because he feels Crookshanks caused Scabbers' disappearance, while Hermione fiercely maintains that Crookshanks is innocent. While filling in for Remus Lupin in one DADA class, Snape labels Hermione "an insufferable know-it-all" and penalises Gryffindor after she speaks out of turn in her attempt to describe a werewolf when no one else does. She correctly deduces