Actor Michael Kenneth Williams, best known for playing 1920s bootlegger Chalky White on "Boardwalk Empire" and thief Omar Little in "The Wire," struggled to land any roles until a near-death incident left a long scar on his face, he recently told the NPR radio program "All Things Considered."

Until his 25th birthday, Williams performed as a backup dancer on music videos. But a barroom brawl on his birthday changed the course of his career.

Williams took a break outside the Queens party and saw two friends surrounded by men he didn't know. He told his friends he wanted to leave, but then one of the strangers confronted him from behind.

"Things changed immediately after [the scar]," says Williams. "Directors didn't want me just to dance in videos anymore. They wanted me to act out these thug rolls." AP "The dude wiped his hand across his mouth and ... smacked me," Williams, 47, told NPR. "What he did was he spit a razor. He was positioning the razor in his mouth to get it between his middle finger and ring finger. And then he swiped me down my face."

The slash has left a permanent scar running down the center of his face, from his forehead down to his right cheek.

"The cut on my face was actually the first hit of the fight, so we managed to escape with our lives, barely, that night," Williams explained. "Things changed immediately after that. Directors didn't want me just to dance in videos anymore. They wanted me to act out these thug rolls. They were like, 'Mike, roll these dice in this video! Have this fight in this video!' I was like, 'All right!'"

Soon he was working on bigger projects. The rapper Tupac Shakur hand-picked Williams for a role as his tough younger brother in the 1996 movie "Bullet."

"He happened to see a polaroid picture of me and was like, 'Yo, this dude looks thugged out enough' ... I think he saw my pain, my struggle, my heart," Williams said.

Next came major supporting roles on TV shows "Law and Order" and "The Sopranos." But Williams was still waiting for his big break. In the meantime, he lived with his mother and was considering working with her at a daycare she opened in a low-income neighborhood.

"My phone did not ring and I was down in the dumps," he said. "I got really depressed. Like, really depressed."

Months later, the big break finally came when Williams received a fax with details about a role he would end up portraying in "The Wire," another tough-guy character named Omar Little who steals from drug dealers.

"I got to grow with an amazing group of people that I consider my 'Wire' family," Williams said. "That character changed my life. And that was my big break."

"The Wire" role led to many more opportunities, including playing Professor Marshall Kane on "Community" and "Chalky White" on HBO's "Boardwalk Empire." Williams currently has eight TV and movie projects in the works for the rest of 2014.