Promises, Promises, Porchlight Music Theatre Chicago, at the Theatre Building Chicago. The basis for this 1968 musical was Billy Wilder’s 1960 film The Apartment, a biting spoof of office politics that sardonically celebrated slick survival. Chuck Baxter is a nebbishy midlevel exec who moves up the corporate ladder by lending his apartment to his superiors for their extramarital trysts. When he acquires his own love interest–executive-restaurant manager Fran–he finally stands up to the suits who’ve screwed them both.

Oddly, the musical version by book writer Neil Simon, lyricist Hal David, and composer Burt Bacharach seems more dated than the film, but its funky score, surefire wisecracks, and compassion for the characters keep the action humming. L. Walter Stearns’s sprightly time-capsule staging fully capitalizes on these strengths. Music director Eugene Dizon peps up the vintage-60s winners, like the pulsating title number and the lilting “Whoever You Are, I Love You,” and Jonathan Osborne makes the costumes period perfect. Mark E. Smith depicts lovable loser Chuck–a square caught in a triangle–with a mannered self-effacement that just skirts affectation. His scenes with Meghan Falica’s winsome Fran would melt a misanthrope, however, never more so than in their low-key version of “I’ll Never Fall in Love Again” (never meant to be a star vehicle). Greg Teghtmeyer brings a bracing dignity to Chuck’s leering boss, a misogynist who could have been too dastardly to be human.