In Germany, a sonically daring Chekhov adaptation and a post-apocalyptic western “opera” are breaking down barriers between genres.FRANKFURT — Ever since Bertolt Brecht and Kurt Weill served up “The Threepenny Opera,” their “play with music,” in Berlin in 1928, the dividing line between spoken and musical theater in Germany has been remarkably porous.Music is everywhere in contemporary German theater, often used to heighten or subvert emotional effects. Some of the credit or blame goes to Frank Castorf, the influential East Berlin director, whose long, demanding productions at the Volksbühne owed much of their unique, frenetic energy to the eclectic soundtracks devised by the theater’s longtime music director, Sir Henry.The quota of live music on dramatic stages here also seems to be increasing. Recent memorable examples have included the furious drumming that provides a rhythmic backbone to the Trojan War segment of Christopher Rüping’s monumental “Dionysos Stadt” and the dronelike chanting in Ulrich Rasche’s takes on classic works.And two of last year’s most discussed shows — Bonn Park’s “Gymnasium” and Yael Ronen’s “Slippery Slope” — were bona fide musicals, with impressive scores and singing, although they were a far cry from your typical Broadway or West End fare. Watching both productions, I felt we might be on the cusp of a breakthrough, with serious theater makers here channeling the vulgar and gleeful tunefulness of “Avenue Q” or “The Book of Mormon.”Such thoughts swirled in my head as I sat down to watch “Burt Turrido. An Opera” in Frankfurt this month. A four-hour post-apocalyptic western, it will travel to Hamburg and Berlin in the coming weeks.Behind the show is Nature Theater of Oklahoma, an influential American avant-garde theater collective that was founded in New York in 2006 and has become increasingly prominent on European stages in the past decade. The troupe’s co-founders, Kelly Copper and Pavol Liska, are serious artists whose shrewd approach and mischievous creative drive combine elements of European and American avant-gardes. Formally daring, energetic and unpredictable, their work is hard to pin down precisely because it encompasses so many genres and styles.From left, Bence Mezei, Robert M. Johanson, Anne Gridley and Gabel Eiben in “Burt Turrido.”Jessica SchäferSadly, the theatrical exuberance and innovation that characterize Copper and Liska’s best efforts are in short supply in “Burt Turrido,” a loopy mock-opera whose silliness would be bearable if the meandering libretto had anything to say, or if the canned score was not a succession of immediately forgettable folk and country tunes.The title character (a bewildered-looking Gabel Eiben) is a red-bearded castaway with amnesia who washes ashore on a barren island. He is rescued by Queen Karen (a scene-chewing Anne Gridley) and King Bob (Robert M. Johanson, who also wrote the music), petty despots who seized control of the island after it was swept by waves of environmental catastrophe, war and genocide. Burt is pursued by Karen, who wants his child, and a lovesick ghost named Emily (Kadence Neill, the cast’s best singer). Oh, and there’s Joseph (Bence Mezei), Emily’s ex-husband and Karen’s ex-lover, who has more than a little in common with his biblical predecessor. (For starters, he’s thrown into a pit.)The characters circle one another in an endless dance of romantic intrigue, suspicion and shifting power dynamics. Copper and Liska keep the tone light, with some silly sci-fi and horror effects (ghosts in sheets; a chintzy U.F.O.) and only a handful of genuinely moving scenes.This is a show with legs: It has already been performed in the Netherlands, Austria, Switzerland, Norway and Greece. (So far, however, no U.S. dates have been announced.) And it does seem to have been devised and designed for maximum portability. Luka Curk’s set consists of little more than flat, hand-painted backdrops, cutout waves jerked back and forth by the performers, and a shimmering blue cloth to represent the sea.Of course, a certain level of flimsiness is precisely the point of this winking, knowing operatic sendup: It’s decidedly a bargain basement production, and Copper and Liska’s ability to create a convincing and clean theatrical aesthetic out of the bare-bones staging is their main achievement here. Yet at even half its current length, “Burt Turrido” would be excruciating. Its 14 scenes (and epilogue) feel like a goofy sketch that has metastasized to operatic proportions.I would have felt bad for the performers who needed to drawl, warble and dance their way through the overlong evening, except that they appeared to be having more fun than the audience, a large portion of which fled at intermission. Beyond the spirited performances, there’s little to recommend “Burt Turrido,” which mostly feels like a joke that goes on far too long. Perhaps the biggest disappointment is how little the music adds. Here, too, the constant singing registers mostly as a gimmick, and there is little flair to Johanson’s score. The result is an impoverished “opera” where neither the music nor the drama is enriched through their combination.The cast of “Waiting for Platonov,” directed by Thom Luz, at the Residenztheater.Sandra ThenFor a sly and haunting marriage of those two elements, turn to “Waiting for Platonov,” an arrestingly musical production by the Swiss director Thom Luz at the Residenztheater in Munich. The title character of Chekhov’s early play, a womanizing schoolteacher who broods on his life of failure, never materializes during the production’s two and a half hours. Instead, a troupe of 10 actors recite snippets of dialogue drawn from the Russian writer’s work and break out in song while performing an energetic choreography that is precisely timed to a witty, inventive sound design.The title, with its nod to Beckett, can be interpreted in several ways. First of all, it proposes the Russian dramatist as a sort of precursor to the Irish Nobel Prize winner in his examination of futility as an existential component of human life. Chekhov’s characters cavort in dachas, while Beckett’s take up residence in trash cans — but they all feel the stifling dread and purposelessness of existence. The title may also refer to the fact that it took over four decades for Chekhov’s 1878 work to be published. The actors’ excitement and increasing exasperation over Platonov’s impending arrival parallels the writer’s frustrations with the play, which was rejected by Maria Yermolova, the great Russian actress to whom he sent the manuscript.Luz, an in-house director at the Residenztheater, brings a compositional rigor to his work that is occasionally reminiscent of the style of Christoph Marthaler and Herbert Fritsch, two influential older directors with keen musical sensibilities and a penchant for absurdity, but his enigmatic and astringent style is entirely his own. The show’s soundscape, devised by Luz, is full of popping mics, uncanny reverberations, sustained clusters of discordant notes and an out-of-tune mechanical piano. As the actors ascend and descend two large onstage staircases (also designed by Luz), their footfalls describe musical scales.Luz balances between the production’s abstract, aural elements and Chekhov’s decontextualized dialogue, which takes on a musical function as well through chanting. Although it is as far from traditional musical theater as “Burt Turrido. An Opera” is from “La Traviata,” “Waiting for Platonov” is a fusion of music, sound and text that is hypnotic, compelling and utterly fresh.Burt Turrido. An Opera. Directed by Kelly Copper and Pavol Liska. Oct. 27-29 at Kampnagel, in Hamburg; Nov. 3-5 at HAU — Hebbel am Ufer, in Berlin; Nov. 11-13 at Espoo City Theater, in Espoo, Finland.Waiting for Platonov. Directed by Thom Luz. Through Dec. 7 at the Residenztheater, in Munich. More