The problem that brought Marty and Doc into the future was that of Marty’s son getting jailed, which is humorously on the front page of USA Today. As the characters discuss how to fix it, the eagle-eyed viewer can pick out a few interesting headlines.
At the top of the Newsline is “Thumb Bandits Strike,” a reference to using your thumbprint to get into your home in the future. There’s also “Man Killed By Falling Litter,” “President Says She’s Tired,” and even “Shredding for Charity.” Plus, at the top of the page, we have some sports headlines: “Slamball Playoffs Begin,” and we really wish we could learn more about that sport, and “Marshall Runs 3 Minute Mile.”
His Shirt Tells the Future
In 2015, Hawaiian shirts are IN. Doc Brown fits in like a charm, throwing on clothes that stand out and blend in just right. However, looking closely tells us that the filmmakers were planning for the third installment of the series while even filming.
The pattern is quite significant. It seems to be a group of men on horseback chasing after a speeding train. While that's a relatively normal Western scene, it's also foreshadowing for what happens in "Back to the Future Part III". It's known that the filmmakers worked on "Part II" and "Part III" at the same time, so this seems quite on purpose.
Another Peek at the Future
When Marty steps into the retro eighties diner in "Part II", there's a wild-west arcade game called "The Wild Gunman", which isn't an actual game. Marty takes the pistol controller from the befuddled young player and blasts the bad guys away, showing off his retro-video game shooting skills.
While the rest of the video games in the diner were real, this one is another reference to what lies in wait for Marty down the tracks of the series in "Part III". The main antagonist of the third film, Mad Dog Tannen, even shares his nickname with the main character of the game.
Fading Away
When old Biff arrives in 1955 to give his younger self the Almanac, he's wincing in pain. Most people assume it's from the DeLorean's shocking ride, but it's actually supposed to be because he's fading away like Marty almost did in the first film.
He's going back to change his own future, which eliminates his own timeline. The rest of the shots of his suffering were cut. Pretty gruesome, now that we think about it – but it takes some time for him to disappear entirely, which allows him to get back to his own time and save himself. We think.
He Makes His Own Time
When Marty finally gets back to 1985, he finds the world turned on its head, with Biff Tannen in control. Biff has killed George McFly, married Lorraine, and amassed endless wealth thanks to the Almanac his elder self came back to give him.
His Hill Valley is completely different, and it's best seen by his decision to get rid of the city hall clock tower. It's the only version of the town seen in all three films with no clock tower. The filmmakers went this route with the Biff timeline on purpose, in order to contrast Marty's effect on Hill Valley as opposed to Biff's.