Between matinee and evening performances of the comedy “Dying for It” at the Atlantic Theater, the British playwright Moira Buffini slouched in a plush seat with a cup of milky tea and squinted up at the ramshackle set. She’d flown into town only the day before to help steer the play, which opens on Jan. 8, through previews. Already she’d hit a roadblock.

“I have to take all the swearing out,” she said. “I think it sounds wrong.”

In Britain, she explained, obscenities are just “salt and pepper” enlivening everyday language. But here, “swearing is really shocking.” (Shh! No one tell David Mamet.)

Pruning back the profanity is a surprisingly decorous gesture from a writer who doesn’t shy away from the vivid and violent, the heightened and intense. Her works, like “Gabriel,” which had a run at the Atlantic in 2010, or “Dinner” and “Welcome to Thebes,” which played at the National Theater in London, are collisions of comedy and tragedy, satire and farce. Terrible things happen, wonderful ones, too. There are big events, big emotions and the occasional influx of lobsters or Nazis. Her characters have juicier things to bite than their tongues.