Namely, that on this day, in 1955, mankind achieved time travel.
Let's hear a word from the great man himself: November 5, 1955! That was the day I invented time-travel. I remember it vividly. I wa standing on the edge of my toilet hanging a clock, the porcelain was wet, I slipped, hit my head on the sink, and when I came to I had a revelation! A vision! A picture in my head! A picture of this! This is what makes time travel possible: the flux capacitor! - Doc Brown
Truly, a great moment in the history of ever.
In the spirit of this international holiday, I offer you the following:
(If you have to guess the source, you have not been paying attention)
Doc Brown: [running out of the room] 1.21 gigawatts? 1.21 gigawatts? Great Scott! Marty McFly: [following] What-what the hell is a gigawatt?
Possibly one of my favorite scenes from the series. Cuz the next line of the movie is
UNLESS YOU GOT POWAHHH.
If my cousin, in