"It ain’t how hard you hit... it’s how hard you can get hit and keep moving forward."

That's one of the most iconic lines from one of the most iconic film franchises of all time.

Rocky really has stood the test of time. It's a true Hollywood blockbuster and a movie every sports fan has to see.

But have you ever wanted to know more about the story behind the making of the original film? Well, you're in luck.

On June 9, a documentary titled '40 Years of Rocky: The Birth of a Classic' will be digitally released.

It will take fans behind the scenes of the 1976 title, with previously unseen footage exploring how Sylvester Stallone went from an unknown actor to one of the biggest stars on the planet.

Rare home footage filmed by director John G Avildsen will also be featured and if that isn't exciting enough, the documentary is narrated by Stallone himself. 

"You're a very lucky person when you can find out that the best friend you ever had is some character that just popped out of your mind," he says in the trailer, which you can see below.

Writer and producer Derek Wayne Johnson also gave more details about what fans can expect next week. 

"The documentary is a golden nugget for Rocky fans and casual audiences alike," he told IndieWire.

"It's a charming piece of film history narrated by Rocky himself, Sylvester Stallone, and will give audiences an intimate, and at times, emotional experience.

"We're proud of the film, and audiences can expect new stories and new footage that they've never seen before in a blend of director John Avildsen's home movies, rehearsal footage, and behind-the-scenes footage from the making of the ultimate underdog film." 

We. Can't. Wait.