One of the best scenes in Back To The Future is when Marty McFly first travels back in time to 1955 and runs to Dr. Emmett "Doc" Brown’s house to tell him he’s from the future. Of course, Doc doesn’t believe him and it leads to this hilarious exchange:

Dr. Emmett Brown: Then tell me, future boy, who's President of the United States in 1985?

Marty McFly: Ronald Reagan.

Dr. Emmett Brown: Ronald Reagan? The actor?

It’s funny in retrospect, but in truth, in 1955, it just didn’t seem possible that an actor like Ronald Reagan would go on to become the most powerful man on Earth (ditto for Arnold Schwarzenegger becoming the Governor of the largest state in the union). But that's what happened.

Over the years, the unlikeliest of rappers have become G.O.A.T. contenders, the most gangster rappers have gone soft, and the epicenter of rap has moved in directions we didn’t even think existed. At this point, nothing would surprise us. We’ve learned to expect the unexpected and never say never. Here are the events that taught us that:

The 20 Hip-Hop Moments We Thought We'd Never See.

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