A ring of invisibility found in a giant fish. A voyeuristic king. A fisherman’s burning house and unfaithful wife. Alexander Zemlinsky’s Der König Kandaules is an exceptionally strange opera. Based on André Gide’s 1899 play of the same title, it is a heady mix of sex, violence, and remarkably beautiful music. In the Volksoper’s remarkable revival, its allusiveness alternately fascinates and alienates, drawing the viewer in only to reward them with yet more mysteries.

Zemlinsky spent his early career, around the turn of the twentieth century, in Vienna. Among other activities, he conducted at the Volksoper. In 1933 he returned to the city, fleeing Nazi-controlled Germany. In the four years before he left Europe altogether, he began Der König Kandaules. It remained unperformed and unfinished at his death in New York in 1942. (It is now heard in an edition reconstructed and finished by musicologist Antony Beaumont.)

The central character is the king Kaudaules, a generous man who wishes to share all he possesses with his subjects. These possessions include his wife, Nyssia, whom he orders to appear in public without her customary veil, prompting odes to her beauty. At the same event, a mysterious ring is found in the giant fish that is being served. “I conceal happiness,” it reads. It also, it turns out, conceals its wearer, who is rendered invisible. Summoning Gyges, the fisher who provided the dinner, Kandaules gives him the ring and invites him to observe Nyssia while invisible and later spend the night with her (whether he then remains invisible is one of the opera’s more mundane mysteries). This, as one can imagine, does not end well.

This is not a complete outline of the plot, even of the first two acts - I neglected to mention the revelation of Gyges’s wife’s infidelity, and his prompt murder of her in front of the court, for example--but provides a glimpse of the opera’s nature. Everything seems to allegorize, but the nature of that significance is never made clear. The characters’ actions are confusing, their inner lives puzzles. Yet the action has a twisted poetry, mostly endowed by Zemlinsky’s impressionistic, lyric score, whose fleeting motives and kaleidoscopic colors seem to fit the unclear action.

The Volksoper’s current revival of Hans Neuenfel’s 1997 production is musically excellent and theatrically exemplary. Neuenfels doesn’t solve the opera’s problems for the audience, and adds a few of his own puzzles of his own as well. The minimal setting consists of a court of elderly, bearded men of unclear time period. The court includes a group of African servants (played by mute actors in obvious blackface), who in the final minutes of the opera form their alliance to the oppressed Nyssia and impoverished Gyges, suggesting a racial, gender, and class message. Neuenfels’s insertion of the wandering mute figure of Alexander Zemlinsky suggests a possible autobiographical significance - the overly generous king as assimilated Jew, defeated by someone whose danger he does not mark. But these implications are left vague.

But the production’s action is detailed, fluid and convincing (such as it can be), and revival director Monika Steiner’s work is unusually good. The cast is also excellent. The standout was Meagan Miller’s luminous, clear soprano in the role of Nyssia, aided by her graceful, natural stage presence. Miller will sing Strauss’s Daphne at the Wiener Staatsoper next season; hers is a career to watch. As Gyges, Kay Stiefermann was appropriately simple and straightforward, and sang with dignified power in a solid baritone. In the title role, Robert Brubaker’s dark, muscular tenor was sometimes uneven, but he sang with impressive volume and made a compelling protagonist. The Volksoper orchestra, led by Alfred Eschwé, did a respectable job with Zemlinsky’s difficult score, and the population of disreputable courtiers lurked appropriately.

Like the ring, Der König Kandaules conceals. Neuenfels’s approach feels true to its elusive heart. For the naturally inquisitive and problem-solving audience member, such as your critic, it can be a frustrating experience. A giant fish with a ring inside simply must mean something, and yet appears not to. Yet the Volksoper has done a great service by bringing this complex, fascinating work back to their stage in such a compelling production.

At the end of the performance, the house was honored with the 2011 Zemlinsky Prize from the Zemlinsky fund of Vienna’s Gesellschaft der Musikfreunde for their promotion of the composer’s work.