Book details

Here's what the actor said

In the video, Stallone said, "This has been an incredibly busy year. I turned 80, which is remarkable, and Rocky turned 50, and I wrote a book. I never thought I'd write this book."

He added that the memoir is like a "secret," a "miraculous journey that was full of struggle."

"And there were so many times I wanted to quit and just give up, but something kept driving me forward, and that's what this story's about."