Seen Off Broadway: The Naked Angels production of Next Fall has proven to be one of the biggest hits of the summer season. Geoffrey Naufft’s play has a sitcom surface that makes irresolvable issues about identity and relationships both entertaining and comprehensible. When a taxi strikes Luke (Patrick Heusinger), his long-divorced parents Butch (Cotter Smith) and Arlene (Connie Ray) rush to his hospital bedside, where they make small talk with his friend and employer Holly (Maddie Corman). Wanting to have a more expansive conversation, but trying to hold back, is Luke’s older lover Adam (Patrick Breen); Luke has kept their lengthy, live-in partnership a secret from his polite, but bigoted, mother and father. Flashbacks reveal the flashpoint in Adam and Luke’s bond: Luke’s Christianity, which he’s reconciled with his homosexuality, much to Adam’s chagrin. Luke’s coma forces Adam to a reckoning.

The unforced acting, and Sheryl Kaller’s sensitive direction, overcome the more obvious touches in Naufft’s writing. These include the names of the three male characters (there is a fourth, Brandon, played by Sean Dugan, who has a single expressive scene) and a tendency to broaden the funnier scenes as much as possible, as when Butch visits Adam and Luke’s not-quite-“de-gayed” apartment. Still, the play doesn’t betray its knotty subject, and gives equal time to all viewpoints, without being patronizing—the secret of its success.

Next Fall is being staged at the most intimate of Playwrights Horizons’ spaces, the Peter Jay Sharp Theatre. Wilson Chin’s set is used mainly as the barebones hospital, with the more detailed apartment and other spaces flying in as needed; the theatre is such that the spine of every book on the shelves can be easily read, and, yes, Luke and Adam have their work cut out for them when it’s time to clean up for Butch’s arrival. Jessica Wegener’s costumes reinforce the characterizations, with the belle-ish Arlene and the new age-y Holly an interesting contrast. Jeff Croiter’s lighting and Bart Fasbender’s sound heighten the emotional impact of sequences without overwhelming them. Next Fall runs through Aug. 8.