The Tom Riddle Chronicles: The Opening of the Chamber of Secrets
Through his research Tom found out about his Slytherin ancestry, and in his fifth year he discovered the existence of the Chamber of Secrets under Hogwarts. Tom was able to open the Chamber and tame the basilisk which dwelt within. The basilisk injured many students, and even killed one student named Myrtle whilst in the girl’s bathroom. Tom used this murder to infuse a journal with a piece of his soul, transforming it into a Horcrux. Hogwarts was set to be closed, but Tom did not want to return to the orphanage, so he framed fellow student Rubeus Hagrid by convincing everyone his pet Acromantula was the monster that terrorised the school. Dumbledore, who seemed the only one to distrust Riddle, kept a close watch on him after that. Tom, however, received an engraved trophy for Special Services to the School.