marty mcfly

I don't know about you, but when I watch Back To The Future it's not the time travel I have issues with. My confusion comes from the fact that a teenager is best friends with a very old man. I mean, we maybe didn't think it was strange the first time we watched it, but as time goes on and you see the movie more and more, you start to wonder how they met. They never really address it in the movies, even though they had three separate chances to even give us a simple sentence like "we met at