What distinguishes a musical from an opera? Many have stumbled over this question, but why get stuck on theory? To American audiences, Sondheim’s shows are musicals, end of story, even if they turn up in the opera house. Abroad, it’s more complicated. Mounted commercially, in the local vernacular, they tend to count as musicals. But maybe when a major opera company presents them in English—the same as they would present Verdi in Italian or Janáček in Czech—the vibe is more operatic? Throwing all such musings into disarray, the Semperoper in Dresden, where Der Rosenkavalier and Elektra saw light, is now presenting Into the Woods “auf deutsch,” thus in populist “musical” mode rather than snooty “operatic.” To judge by the online teaser, the lyrics don’t scan so great. On the other hand, the jazzy Weimar-goes-Broadway look of the show seems, for local consumption, spot-on. Manfred Weiss directs. —Matthew Gurewitsch