'Boardwalk Empire' Season 4 Trailer: 'No Reign Goes Unchallenged' (VIDEO)

The "Boardwalk Empire" Season 4 trailer has arrived, which is bad news for Nucky Thompson's enemies.

The trailer opens with a bootlegging middle-man unsuccessfully pleading for his life, while a judge asks Gillian Darmody, "What exactly happened in your residence eight months ago?" Richard Harrow single-handedly killed 15 of Gyp Rosetti's men, that's what. But it is being described as an "unsolved gangland shootout."

Nucky Thompson, for his part, explains, "I didn't ask for trouble. When it was brought to my doorstep, I returned."

There's a montage of mob violence set to the sounds of Atlantic City ladies tap dancing, and we see Richard Harrow, Capone's Chicago crew and Chalky White's guys perpetrating all kinds of gangster violence.

We also meet the show's two newest characters, Jeffrey Wright's Dr. Arnold Narcisse, a doctor of divinity who controls Harlem, and Ron Livingston's Roy Phillips, a ladies man who comes down to Atlantic City and befriends Gillian. Dr. Narcisse (don't call him Mr.) says, "Only kings understand each other," but Nucky seems reluctant to continue doing business in person. "What shall we do, Mr. Thompson, what shall we do?" Narcisse intones.

The trailer also includes the slogan, "No reign goes unchallenged." It's going to be an interesting season.

"Boardwalk Empire" Season 4 premieres Sunday, September 8 on HBO.