'Boardwalk Empire' Season 4 New Trailer "No Reign Goes Unchallenged" / Dr. Narcisse Joins Cast / Premiere Date September 8 on HBO [VIDEO]

The new trailer for Boardwalk Empire Season 4 is comforting. Not comforting in the way of a home-cooked meal or a freshly mowed lawn. The "No Reign Goes Unchallenged" trailer is comforting in the way that let's you know your favorite early American crime-mob show is only getting more intense than ever in its fourth season.

Nucky Thompson and the Atlantic City crime scene returns to HBO September 8 at 9 PM ET for the Season 4 premiere.

The year is 1924 and it looks like Nucky has more problems in New York than just Arnold Rothstein. New player Dr. Valentin Narcisse out of Harlem will play a big role in Season 4. Something tells me Narcisse, played by the smooth talking Jeffrey Wright, isn't going to play nice.

"Only kings understand each other," Narcisse says. "What shall we do, Mr. Thompson?" asks a threatening Narcisse by a roaring fire in what looks like Nucky's quarters.

The ever-stressed Nucky Thompson seems as hard-pressed as ever in the latest trailer. Weaved into a montage of men falling from buildings and cops getting shot, Steve Buscemi's voice can be heard asking:

"You ever wake up and have a vague feeling of unease?" Nucky says, before closing the end of the trailer confessing that, "the only thing you can count on is blood."

In case you didn't see, HBO recently released an awesome Boardwalk Empire Season 4 poster online featuring Nucky Thompson, Chalky White and Eli.

Tune in for the Boardwalk Empire Season 4 premiere on HBO Sunday, September 8 at 9 PM E.S.T.

"No Reign Goes Unchallenged" trailer preview: