Their conversation was overheard by Thorin, confirming his doubts and suspicions about the Hobbit.As Bilbo was about to leave, his Sting sword blade glowed blue - indicating the presence of Goblins.The group fell hrough the cave's floor into deep passageways, where they were quickly besieged by growling Goblins.Entering into the room wasthe main protagonist - skateboard-riding, guitar-playing, Hill Valley high-school student Martin "Marty" Seamus McFly (Michael J.P.- it spurred a flashback to some cheerful youthful family days when he was being playful with his father.The next morning before a judge, Thornhill's lawyer argues that "would-be assassins" gave chase and he had to drive "as best he could under the, uh, circumstances.