Back to the Future theory: Why Doc Brown changed his mind and read Marty McFly’s letter

Four years ago today, Doc Brown, Marty McFly and Jennifer arrived in the future. Well, a version of it with flying cars and hoverboards that we’re still waiting for. Yes, today is Back to the Future Day and what better way to celebrate than with a pretty cool new fan theory about the original movie. Have you ever wondered why Doc changed his mind about reading Marty’s letter?

Fans will remember Marty wrote a letter to Doc in Lou’s Cafe on November 12, 1955 – the night he went back to the future after the clock tower was struck by lightning at 10:04pm.

The young time traveller was concerned for 1955 Doc’s future, knowing that the night be went back in time 1985 Doc would be shot by Libyan terrorists.

So to prevent his death, Marty wrote him the letter with instructions on the envelope not to be opened until 1985.

However, 1955 Doc was concerned about disrupting the timeline and ripped it up.

When Marty arrived back in 1985, having hoped to save Doc by arriving before he left, he was too late.

Nevertheless, 1985 Doc was found unscathed, having worn a bulletproof vest since he read the letter.

READ MORE: BACK TO THE FUTURE THE MUSICAL DEBUTS 2020

Asked why he changed his mind, Doc simply said: “I figured, what the hell?”

This may seem a bit unconvincing to some fans, considering how careful Doc is to avoid paradoxes – well, until he falls in love with Clara in Part III anyway.

Now a new fan theory claims that Doc read Marty’s letter because he was visited by Marty again moments after sending his past self back to the future, at the end of Part II.

Reddit user HBBrian writes: “The only explanation for this would be that, he wasn’t inspired til after the moment Marty from the future revisited him in 1955 and showed him the letter that he wrote to Marty from 1885.

“To me this would explain why Doc would bother to tape the letter and preserve it because it’s crucial that he stay alive to be able to go to the future the first time, to come back and warn Marty about his future trying to fix it thus creating the paradox.”

It’s true. If Doc was shot in 1985, Marty’s return to 1955 in Back to the Future Part II would never have happened.

Ironically, reading Marty’s letter actually prevented a paradox rather than create one.

Meanwhile, another fan theory explains why Marty couldn’t start the DeLorean time machine in Back to the Future.

They argue it was thanks to interference from past and future versions of the same car that appear and disappear around the same point in time.

To read this epic theory, click here.