“Pal Joey” was a perfect choice to close out the series’s second season. The masterpiece of the long collaboration between composer Richard Rodgers and lyricist Lorenz Hart, the 1940 show shook up Broadway with its John O’Hara book that swept sugar off the stage in favor of sin. In “Encores,” Peter Gallagher played Joey Evans, the small-time hoofer/emcee whose studly talents earn him a temporary place in the bed and bankbook of rich bitch Vera Simpson. In the current Disneyfication of Broadway, it was a kick to drink in LuPone’s showstopping “Bewitched,” with its Hart-felt lyrics celebrating a woman’s pure sexual pleasure (“Horizontally speaking, he’s at his very best”). Bebe Neuwirth restopped the show with “Zip,” the anthem of a lady journalist doing a striptease while skewering the intellectual pretensions of the time. Not even Mozart and Da Ponte ever put such levels together in one number.

Restoring such treasures is the aim of “Encores,” the brainchild of City Center executive director Judith Daykin. The shows, three each season in four performances, are done with minimal but evocative sets and costumes, with the east holding script books just in case. A huge plus is the onstage presence of musical director Rob Fisher leading the superb Coffee Club Orchestra. There’s a splendid chorus and a strong, if necessarily limited, dance presence such as “Pal Joey’s” Vicki Lewis leading top Broadway gypsies in the scathing takeoff on gooky love songs “The Flower Garden of My Heart.”

“The focus is music by great Broadway composers,” says “Encores” artistic director Walter Bobble. “We look for shows that have terrific scores with books that am not necessarily revivable today.” Bobble and Fisher use the original orchestrations, which often involves some archeological toil. For Cole Porter’s 1950 show about Greek gods, “Out of This World,” says Bobble, “we had five people day and night gluing together pieces of the score.” Concert versions of shows are hardly new, but, says Bobble, “we’ve brought theater sensibilities to the concert form.” Playwright Terrence McNally came in to “wield a loving scalpel” on O’Hara’s book for “Pal Joey.”

The success of “Encores” has attracted performers like LuPone and Tyne Daly, who was admirably ambassadorial in Irving Berlin’s 1950 “Call Me Madam.” And the estates of composers and lyricists, protective and wary about granting rights (the Kurt Weill estate wouldn’t allow key changes for last season’s Encore of “Lady in the Dark”) are now calling Bobbie to discuss possible productions. “Encores” is as close to a labor of love as the theater gets. Everyone works for scale; the annual budget of $1 million comes from sources like American Express and Andrew Lloyd Webber. Part of it goes to an outreach program for young people. “We bring in high-school kids and give them a musical director and choreographer to do their own version of the shows,” says Bobble. “Then that night they go to see the dress rehearsal of our show. Last week I saw 50 kids in front of a big mirror doing ‘Plant You Now, Dig You Later.’ It was a riot.”

Critical purists cavil at some details: tiny Andrea Martin as Juno, matriarch of the Gods, in “Out of This World”; a director, Jerry Zaks, playing Mayor La Guardia in last year’s “Fiorello! “; LuPone too campy in “Pal Joey.” But Martin was hilarious, Zaks was positively electable, LuPone was the perfect slumming predator. “Encores” cuts to the heart of the matter: no fat, no Broadway baloney. Just the sound of the American heartbeat when it really had rhythm.