Earlier this year Henry, a new restaurant in the lobby of the Life Hotel on West 31st Street, quietly died. You wouldn’t know it to look around the place on any recent night at 8, when a seamless playlist of hip-hop and R&B unspools as servers carry stacked beef ribs to what seems like every third table.

What changed? In August, the chef Joseph Johnson, better known as JJ, was made a partner and assumed control of the kitchen. What he has done is less a makeover than a takeover; his imprint radiates out from his Afrocentric menu to animate the whole enterprise. The playlist, which can run from noon until 8 the next morning without repeating a track, is his. Mr. Johnson’s initials now hang in the front window, flooding the nearby tables with pink neon. The initials have migrated to the restaurant’s website as well, where its name is now given as Henry at Life Hotel by JJ. These are not subtle gestures, but subtlety has rarely saved a restaurant on the brink of failure.

Mr. Johnson has been busy hiring new employees for the front and back of the house, and the racial mix he has already achieved is as impressive as it is rare. Diversifying a restaurant’s service staff is one of the surest ways to diversify the audience, and on many nights brown faces and white faces, topknots and braids, headscarves and headbands, sit side by side, giving Henry more the appearance of a restaurant in Harlem than of one just off Herald Square.

It was in Harlem, as chef de cuisine at a slinky neighborhood hangout called the Cecil and the history-drenched jazz supper club Minton’s, that Mr. Johnson made his name. Fleshing out a notion suggested by Alexander Smalls, the consulting chef in both places, Mr. Johnson explored the African diaspora, the imprint that Africans have put on cooking around the world. He does something similar at Henry, although his view has grown to embrace flavors from, say, India and Southeast Asia that turn up in Africa and in diasporic countries like Jamaica and Barbados. He calls the menu at Henry “Pan-African.”