One or two other things have also changed this season, and that’s a good thing. “Boardwalk Empire” has struggled with go-nowhere plotting and oppressive 1920s artifice over the years, particularly after Michael Pitt’s brooding Jimmy Darmody was killed. For all the commanding acting by Steve Buscemi and all the unexpected plot turns, the drama has never found a consistent overall groove. It goes in and out of greatness, as the ferocious gangster material sometimes devolves into confusion and the intriguing personal stories fail to build.
The most promising addition this season is Jeffrey Wright. He plays a fierce, intellectual gangster from Harlem with the provocative name of Dr. Valentin Narcisse who has contempt for white people and for black people who are subservient to whites. Full story for BostonGlobe.com subscribers.