Draco attended Hogwarts School of Witchcraft and Wizardry from 1991-1998. He was sorted into Slytherin House the moment the Sorting Hat touched his head. During his years at Hogwarts, he became friends with Vincent Crabbe, Gregory Goyle, Pansy Parkinson, and other fellow Slytherins, but he quickly developed a rivalry with Harry Potter.

Much of Draco’s behaviour at school was modelled on the most impressive person he knew – his father – and he faithfully copied Lucius’s cold and contemptuous manner to everyone outside his inner circle. Having recruited a second henchman (Crabbe being already in position pre-Hogwarts) on the train to school, the less physically imposing Malfoy used Crabbe and Goyle as a combination of henchman and bodyguard throughout his six years of school life.

Draco’s feelings for Harry were always based, in a great part, on envy. Though he never sought fame, Harry was unquestionably the most talked-about and admired person at school, and this naturally jarred with a boy who had been brought up to believe that he occupied an almost royal position within the wizarding community. What was more, Harry was most talented at flying, the one skill at which Malfoy had been confident he would outshine all the other first-years. The fact that the Potions master, Snape, had a soft spot for Malfoy, and despised Harry, was only slight compensation.

Draco resorted to many different dirty tactics in his perpetual quest to get under Harry’s skin, or discredit him in the eyes of others including, but not limited to, telling lies about him to the press, manufacturing insulting badges to wear about him, attempting to curse him from behind, and dressing up as one of the Dementors (to which Harry had shown himself particularly vulnerable). However, Malfoy had his own moments of humiliation at Harry’s hands, notably on the Quidditch pitch, and never forgot the shame of being turned into a bouncing ferret by a Defence Against the Dark Arts teacher.He also got punched by Hermione Granger in their third year.

While many people thought that Harry Potter, who had witnessed the Dark Lord’s rebirth, was a liar or a fantasist, Draco Malfoy was one of the few who knew that Harry was telling the truth. His own father had felt his Dark Mark burn and had flown to rejoin the Dark Lord, witnessing Harry and Voldemort’s graveyard duel.

The discussions of these events at Malfoy Manor gave rise to conflicting sensations in Draco Malfoy. On the one hand, he was thrilled by the secret knowledge that Voldemort had returned, and that what his father had always described as the family’s glory days were back once more. On the other, the whispered discussions about the way that Harry had, again, evaded the Dark Lord’s attempts to kill him, caused Draco further twinges of anger and envy. Much as the Death Eaters disliked Harry as an obstacle and as a symbol, he was discussed seriously as an adversary, whereas Draco was still relegated to the status of schoolboy by Death Eaters who met at his parents’ house. Though they were on opposing sides of the gathering battle, Draco felt envious of Harry’s status. He cheered himself up by imagining Voldemort’s triumph, seeing his family honoured under a new regime, and he himself feted at Hogwarts as the important and impressive son of Voldemort’s second-in-command.

School life took an upturn in Draco’s fifth year. Although forbidden to discuss at Hogwarts what he had heard at home, Draco took pleasure in petty triumphs: he was a Prefect (and Harry was not) and Dolores Umbridge, the new Defence Against the Dark Arts teacher, seemed to loathe Harry quite as much as he did. He became a member of Dolores Umbridge’s Inquisitorial Squad, and made it his business to try and discover what Harry and a gang of disparate students were up to, as they formed and trained, in secret, as the forbidden organisation, Dumbledore’s Army. However, at the very moment of triumph, when Draco had cornered Harry and his comrades, and when it seemed that Harry must be expelled by Umbridge, Harry slipped through his fingers. Worse still, Harry managed to thwart Lucius Malfoy’s attempt to kill him, and Draco’s father was captured and sent to Azkaban.

He was made a prefect of his house and was a member of the Inquisitorial Squad during his fifth year, at the end of which his father was imprisoned in Azkaban following the Battle of the Department of Mysteries. Lord Voldemort charged Draco with making up for Lucius's failure, and he became a Death Eater at age sixteen but was quickly disillusioned with the lifestyle.

Draco’s world now fell apart. From having been, as he and his father had believed, on the cusp of authority and prestige such as they had never known before, his father was taken from the family home and imprisoned, far away, in the fearsome wizard prison guarded by Dementors. Lucius had been Draco’s role model and hero since birth. Now he and his mother were pariahs among the Death Eaters; Lucius was a failure and discredited in the eyes of the furious Lord Voldemort.

Draco’s existence had been cloistered and protected until this point; he had been a privileged boy with little to trouble him, assured of his status in the world and with his head full of petty concerns. Now, with his father gone and his mother distraught and afraid, he had to assume a man’s responsibilities.

Worse was to come. Voldemort, seeking to punish Lucius Malfoy still further for the botched capture of Harry, demanded that Draco perform a task so difficult that he would almost certainly fail – and pay with his life. Draco was to murder Albus Dumbledore – how, Voldemort did not trouble to say. Draco was to be left to his own initiative and Narcissa guessed, correctly, that her son was being set up to fail by a wizard who was devoid of pity and could not tolerate failure.

Furious at the world that seemed suddenly to have turned on his father, Draco accepted full membership of the Death Eaters and agreed to perform the murder Voldemort ordered. At this early stage, full of the desire for revenge and to return his father to Voldemort’s favour, Draco barely comprehended what he was being asked to do. All he knew was that Dumbledore represented everything his imprisoned father disliked; Draco managed, quite easily, to convince himself that he, too, thought the world would be a better place without the Hogwarts Headmaster, around whom opposition to Voldemort had always rallied.

Draco was unable to complete his task of murdering Albus Dumbledore, which was later taken over by Severus Snape, and only performed his other duties fearfully and reluctantly. He and his family defected hours before the end of the Second Wizarding War, fearing for their lives.

Voldemort and Snape underestimated Draco. He proved an adept at Occlumency (the magical art of repelling attempts to read the mind), which was essential for the undercover work he had undertaken. After two doomed attempts on Dumbledore’s life, Draco succeeded in his ingenious plan to introduce a whole group of Death Eaters into Hogwarts, with the result that Dumbledore was, indeed, killed – though not by Draco’s hand.

Even when faced with a weak and wandless Dumbledore, Draco found himself unable to deliver the coup de grâce because, in spite of himself, he was touched by Dumbledore’s kindness and pity for his would-be killer. Snape subsequently covered for Draco, lying to Voldemort about Draco lowering his wand prior to his own arrival at the top of the Astronomy Tower; Snape emphasised Draco’s skill in introducing the Death Eaters into the school, and cornering Dumbledore for him, Snape, to kill.

When Lucius was freed from Azkaban shortly afterwards, the family was allowed to return to Malfoy Manor with their lives. However, they were now completely discredited. From dreams of the highest status under Voldemort’s new regime, the Malfoys found themselves the lowest in the ranks of the Death Eaters; weaklings and failures, to whom Voldemort was henceforth derisive and contemptuous.

Draco’s changed, yet still conflicted, personality revealed itself in his actions during the remainder of the war between Voldemort and those who were trying to stop him. Although Draco had still not rid himself of the hope of returning the family to their former high position, his inconveniently awakened conscience led him to try – half-heartedly, perhaps, but arguably as best he could in the circumstances – to save Harry from Voldemort when the former was captured and dragged to Malfoy Manor. During the final battle at Hogwarts however, Malfoy made yet another attempt to capture Harry and thereby save his parents’ prestige, and possibly their lives. Whether he could have brought himself to actually hand over Harry is a moot point; I suspect that, as with his attempted murder of Dumbledore, he would again have found the reality of bringing about another person’s death much more difficult in practice than in theory.

Draco survived Voldemort’s siege of Hogwarts because Harry and Ron saved his life. Following the battle, his father evaded prison by providing evidence against fellow Death Eaters, helping to ensure the capture of many of Lord Voldemort’s followers who had fled into hiding.