If any Broadway musical could hold its own with the opera crowd, it’s “Sweeney Todd.” Performed on opera stages from Wales to Frankfurt in recent years, it’s set to open this season at the New York City Opera. Based on a 19th-century “penny dreadful,” about a Fleet Street barber who slits his customers’ throats, the musical’s themes include cannibalism, Victorian pseudoscience, onanism and capitalism. Its gorgeous, complex score, notes musicologist Stephen Banfield, includes nods to Stravinsky, Shostakovich and a creepy homage to Bach’s “St. Matthew Passion,” sung by Londoners gorging on pies made from human flesh. As directed by Australian Neil Armfield, the current London production, playing until mid-January for nine performances only, bears the hallmarks of opera rather than a long-running extravaganza musical: it’s visually stark, with a few cages and curtains used to create most of the stagings, and relentlessly dark.

The logistics of producing sophisticated musicals like “Sweeney Todd” means that increasingly their future may lie in opera houses. La Scala in Milan has done “West Side Story,” and the New York City Opera recently did Sondheim’s “A Little Night Music,” which New Zealand’s Canterbury Opera will also produce this spring. According to Paul Gemignani, conductor of the current production, cost cutting has meant the scaling down of orchestras in musical theater. For proper sound, shows like “Sweeney” require opera-scale orchestras.

These two old-fashioned art forms–the opera and the musical–might reinvigorate each other. Opera houses are looking to expand beyond classical operas, notes Covent Garden’s opera director Elaine Padmore. Opera companies have thrived in recent years by sticking to old standards like “The Magic Flute” –or putting on sophisticated musicals. Some critics of musicals fret that artistic development has been stunted by long-running blockbusters like “Phantom of the Opera” and “Miss Saigon.” In London’s West End, the new hits are pop-inspired crowd pleasers like “Tonight’s the Night,” based on Rod Stewart songs, and “Mamma Mia,” a confection spun from Abba hits. “A product will just become a kind of sight, like the Eiffel Tower, which you must go and see,” notes Banfield. “When it gets like that, what is its relation to live critical theater?”

Taking refuge in opera houses could mean new audiences for less flashy productions. Wagner aficionados with season box seats will discover the joys of Sondheim and Gershwin; Rodgers and Hammerstein fans, on the other hand, may learn the pleasures of “Carmen.” The nature of opera-house productions, driven by powerful creative teams, might also create an artistic renaissance for musicals, which often merely re-create the emotions of movies people remember from childhood. “When a musical is produced in an opera house, it becomes a different level of intellectual property,” says Padmore. “It’s becoming a masterpiece, so you want to take it and play with it.” If that means live-and-kicking musical theater and opera–play on.