Happy Back to the Future Day!

Credit: Universal Studios
Credit: Universal Studios

Oct. 21 is the day that Marty McFly and Doc Brown arrived in the year 2015 after traveling forward in time from 1985. From this day forward, everything that happened in Back to the Future will have happened in the past. This will undoubtedly create temporal paradoxes throughout this and any other parallel time lines that may exist. God only knows what could happen.