He is voiced by Sean Connery.
Draco first appears in a cave where he is approached by Prince Einon's mother Queen Aislinn and Sir Bowen, who implore Draco to save Einon's life. Draco however, can sense the evil in Einon's heart, and is therefore reluctant to help, also knowing that Einon's father was a cruel and brutal warlord. Eventually though Draco agreed to save Einon, hoping that his heart could make Einon a better person. Instead, Einon proved to be no better after getting half of Draco's heart, and went on to become just as evil as his father ever was. Horrified at his actions, Draco retreated, also being pursued by Bowen, who believed that Draco's heart had made Einon evil.
For 12 years Draco fled and hid, watching as his fellow dragons were slain until eventually he was the only one left. Pointing out to Bowen that if the former knight kills him he will be out of a job, the two instead agree to work together and con villages by having Draco attack them and then pretend to be slain by Bowen. As the two continue this scheme, they come to develop a genuine friendship, with Draco first getting this name from Bowen (his real name is, according to Draco, unpronouncable for humans). Draco also explains that only sufficiently viruous dragons get to go to their heaven, and that all others simply "disappear" when they die. Because Draco saved the life of a wicked individual, and used his own heart to do it, he knows full well that he will never be able to ascend.
Draco helps Bowen and his friends formulate a rebellion against Einon, but due to sharing a link with him in which they can feel each other's pain, it becomes clear that Einon cannot die so long as Draco lives. As a result, Bowen is ultimately forced to kill his friend to stop Einon. But in having given his life to stop Einon, Draco has sufficiently redeemed himself and his soul is allowed to ascend to the Dragon's heaven, becoming the very brightest of the starts in it.
In the 2000 sequel Dragonheart: A New Beginning, it is revealed that prior to his death, Drago had an egg which hatched into Drake.