On March 7, 1987, 20-year-old Mike Tyson walked into the Las Vegas Hilton as the WBC heavyweight champion, looking to take another step toward becoming the undisputed king of the division.

Standing across from him was James “Bonecrusher” Smith — the WBA heavyweight champion, a former U.S. Army serviceman, and a former prison guard from North Carolina.

Smith wasn’t just another opponent. He was bigger, older, physically strong, and hardened by a life far different from most fighters Tyson had faced. Before the bright lights of championship boxing, he had served overseas, fought in military tournaments, and later worked inside the correctional system.

But against Mike Tyson, intimidation was never simple.

This is the story of the night Tyson fought a prison guard — and moved one step closer to becoming the undisputed heavyweight champion of the world.