One of the most beloved aspects of the 1985 classic, Back to the Future, is the dynamic between the teenage Marty McFly and the wacky yet brilliant Doctor Emmett Brown. Of course, this strange relationship over the years has frequently raised the question of how a high school kid became friends with a mad scientist. Finally, in the 2015 comic book, Back to the Future #1, the answer to this age-old query was revealed.
Before delving into how Marty and Doc became friends, it's important to understand the nature of their relationship. At the start of Back to the Future, Marty is depicted as Doc's only friend, save for his dog, Einstein. The film opens with an illustration of this friendship when Marty arrives at Doc's house. Marty is there to check in on Doc, as the genius scientist has been missing for days. Even when no one else seems to care for Doc's welfare, Marty takes the time before school to visit his friend. This demonstrates Marty and Doc's bond as two outsiders. Marty is plagued by the oppressive principal at school and his depressing family at home, while Doc is largely dismissed as a madman in the community.
Together, the two friends make each other's lives a little easier and more exciting. Marty, from the start, is the eager, wide-eyed observer of Doc's experiments, sort of like an unpaid intern. The reveal of Doc's time machine leaves Marty practically speechless, showing the sense of wonder that Doc instills in his life. Yet Doc is also greatly impacted by his relationship with Marty as well. Without Marty, Doc would have no one to whom he could explain his crazy inventions, or test his wild theories. The friendship between Marty and Doc is the perfect match.
This relationship is explained in a short story called "When Marty Met Emmett," by Bob Gale, John Barber, and Brent Schoonover. In this tale, Marty is forced by the school bully, Needles, into getting an interlocutor tube for his guitar amplifier. Finding nothing at the store, Marty discovers that Doc Brown has what he's looking for, although he is warned that Doc is crazy, a common belief by the people of Hill Valley. Arriving at Doc's house, Marty is forced to overcome a series of traps, testing his wits and his resolve. Here, Marty illustrates his quick thinking, keeping up with Doc's wild ideas and inventions. Arriving in Doc's lab, Marty is asked by the scientist if he was there for an internship position, possibly a nod to Marty's intern-like tasks which he carries out in the film. Marty initially tries to fake interest in the position, before quickly admitting that he was there for the tubes.
Doc humorously reveals that there was no position in the first place, to Marty's confusion. Of course, Doc offers Marty a job running errands for him, to which Marty happily agrees. Marty then discovers that Doc threw out the tubes, only needing the box for his latest invention. Doc lets Marty take the tubes from the trash, setting up their unusual yet mutually beneficial friendship.
Delivering the tubes to Needles, Marty reveals that he got them from Doc Brown, who Needles fears could be radioactive. This light-hearted ending shows how Doc makes Marty's life a little easier and more fun. Marty and Doc's relationship may seem rather unorthodox, but it's for this reason that the two friends work so well together.