Martin McFly Jr.

Martin Seamus 'Marty' McFly Junior (April 28, 1998) is the son of characters Marty McFly and Jennifer Parker in the Back to the Future film trilogy. His personality is not made very clear in the film, but it is established that he is, in the words of his future father, an absolute wimp.

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Pre-Back to the Future Part II

However little is known from before the second movie, we do know that he is born in the late 1990s. His parents are Marty McFly Senior and Jennifer Parker, and he has one sibling: Marlene. While growing up, he's not inspired by his depressed parents at all, resulting in him being similar to his grandfather George, a wimp. Sometime before 2015, most likely a few years before, he starts being pushed around by Griff Tannen and his gang. Not being able to stand up to them, he starts being pushed around even further.

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Back to the Future Part II

On Wednesday, October 21st, 2015, in the original timeline, Marty Junior's life changed drastically. That day, he was asked by Griff Tannen at the Café 80s to participate in a crime. Marty Jr. tried to protest, but finally he gave in to them.

That evening, Marty Junior was caught after committing the crime at 1:28am. He claimed that he didn't know that he was doing anything illegal, and told the police that Griff Tannen and his gang were behind it. Griff, however, denied everything they said, calling Marty Junior a 'low-rez'. After two hours, Marty Jr. was convicted and sentenced to fifteen years in prison, making front-page news the next day with the article 'Youth Jailed: Martin McFly Junior Arrested For Theft'. A few days later, Marlene was caught trying to break him out of jail, and was sentenced to twenty years.

Then Dr. Emmitt Brown came along in October of 2015, and discovered what happened. He did some research, acquired walkie-talkies, binoculars, a good version of the jacket Marty Junior was wearing on the twenty-first (Junior's auto-fit was broken), modified his DeLorean so it could fly, got it a hover-conversion and possibly talked to Marty Senior about what happened. After an unknown time of searching for clues, Doc settled on the plan to let Marty '85 take his son's place, then headed back in time to October 26th, 1985, in the early morning, to change the world.

Marty '85 made it into the Café 80s before Junior, who was knocked-out by Doc's sleep-inducer. Unfortunately, the inducer wasn't fully charged, and he made it to the Café after all. After getting abused by Griff, Marty '85 took his place again, and participated in a hoverboard-race that caused Griff Tannen and the gang to break through the Courthouse windows and get arrested instead. The newspaper properly changed to read 'Gang Jailed: Hoverboard Rampage Destroys Courthouse'.

Marty Jr, unaware of that, exited the Café, puzzling Old Biff Tannen for a moment because he could clearly see Marty '85 on the other end of the street, then passed a driving car and headed towards his home, where he watched TV for a moment, before he had to stop because they were eating pizza. He passed his mother on his way home, unaware that it was her 1985 counterpart.

Shortly after 7:28 PM, we don't know anything about Junior anymore, as the time travellers leave 2015, which has transformed into 2015-A by the time. We don't know anything about Marty Junior in this reality, not even if he exists, so we won't even get started on that part.

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Post-Back to the Future Part III

Little is known about Marty Junior's life after Part III. What is known is that his father, Marty Senior, obviously got over his chicken problem in this new timeline, and therefore might become more successfull. At the end of the trilogy, it is hinted that the future looks bright for Marty and Jennifer, which means that it most likely does for Marty Junior, too.