“The cabaret scene is quite a good one these days,” Mr. Viertel said. “But we are going to be different, particularly in our orientation. The bigger rooms that we might compete with, the Café Carlyle and Feinstein’s, are on the East Side. We aim to be part of the world of Broadway.”

54 Below’s Broadway pedigree extends beyond its owners to the designers: Mr. Beatty and Mr. Billington are both Tony Award winners, and the sound designer, Peter Hylenski, is a Tony nominee. The architect is Richard H. Lewis, who collaborated on the restaurants Bond 45 and Brooklyn Diner with Mr. Beatty.

To help Mr. Beatty conceive the space, Mr. Viertel wrote him a story about a group of thieves whose hideaway morphs into a speakeasy. During a tour last week the story line was apparent in the space, which was still a work in progress. Patrons will enter the club by descending a long, dramatic staircase. In the main rectangular room the walls, chairs and artwork are saturated in deep shades of red, purple and brown, mixed with wood and leather. Shaded lamps light the booths. Cabaret seating accommodates about 140, and at house right, a small bar seats up to 16.

“Patti doesn’t normally sing for under 200 people,” said Scott Wittman, the “Hairspray” lyricist who is the club’s creative consultant and the director of Ms. LuPone’s show. “It’s really like having Patti sing in your living room.”

The club will be open seven days a week with two shows most evenings; bar and food service will be available during and after performances. Mr. Wittman said the performers would be asked to do new material.

“That’s one of the things that we have insisted on,” he said. “If you play the room, it has to be an act created for us. Because we are new, you need to be new.”