The final exams are over, but the pain on Harry′s forehead doesn′t faint. He cannot calm himself down by the thought that it is only because of the exams. He tries to convince himself that the Philosopher′s Stone is save, because nobody is able to pass the three-headed dog.
Harry, Ron and Hermione find out that Hagrid told the person, from whom he got the dragon egg, how to let Fluffy, the three-headed dog, fall asleep. Harry tries to contact Professor Dumbledore, but he is not in school at the moment.
Now Harry decides to go to the trapdoor the same evening, to protect the stone. Ron and Hermione follow him.
The three-headed dog sniffs for them as soon as they come into the corridor. Harry starts to play the flute and the dog falls asleep. They find a harp between his legs and so they know that the thief has already passed the dog. Harry, Ron and Hermione follow him down the trapdoor. The strange soft bounce soon becomes their inevitable fate. But Hermione quickly finds out how to pass the dangerous clasping plant. After difficulties with Ron they continue their way which leads them now to flying keys. This task is also successfully mastered and they are welcomed by chessmen. An exciting and sacrificing game of chess begins and on the end only Harry and Hermione can go on. But the last task also separates them and Harry discovers who is actually after the stone.
