To appreciate the fucked-upness of Verdi’s beautiful tragedy Don Carlo, one would have to get into the head of Friedrich Schiller, who wrote the dramatic poem on which it was based. Clearly, he thought he had hit on the perfect setting for a historical romance: the Spanish Inquisition. But there was something missing. “What could I add to heighten the passion?” he must have thought. “I know. Incest.”

If that would not have been your first impulse, you might not be a fan of opera, or German Romanticism: Incest also plays a key role in Wagner’s Ring Cycle, which the Washington National Opera staged in 2016. Unlike that later epic, Schiller’s play and Verdi’s opera revolved around a somewhat less gross relationship, between stepmom and stepson, an acceptable enough taboo to be a modern-day porn motif. Consider yourself lucky to be spared The Ring’s hot sister-on-brother action on which Wagner chose to base his Teutonic origin myth, something the Nazis, who so loved both racial origin myths and Wagner, seemed to have missed.

That this incestuous romance isn’t real only adds to the absurdity of Don Carlo: There’s no record of the titular character, the son of Spain’s King Philip II, having an affair with Queen Elisabeth of Valois. Yet if Schiller or Verdi had bothered to look for real examples of inappropriate relationships in the House of Habsburg, they wouldn’t have had to invent one. The whole dynasty was inbred to the point that it died out because of it. At the height of their sordid reign, which at one time covered most of Europe, its members were beset by mental illness, and so deformed that they were unable to chew their own food, constantly drooling due to their tongues being so abnormally large. Imprisoned by his father until his death, the real Don Carlo’s problem had nothing to do with sex: He was, by all accounts, simply insane.

Verdi sets his not particularly accurate nor scintillating love triangle in Counter-Reformation Spain, and throws a gratuitous auto-da-fé torture scene in for good measure. In this revisionist history, Prince Carlos, a real-life sadist who liked to cook animals alive and once forced a cobbler to eat boots he deemed unsuitable, is a heroic figure, a champion of liberty for the oppressed subjects of his father’s empire. His affections for his stepmom are merely a manifestation of his sensitive nature. And she reciprocates in explicitly Freudian terms: “Kill your father and lead me to the altar,” she implores. But first, he must lead the Flemish to independence in the Dutch revolt, which was actually led by William of Orange and happened after Carlos died. Director Tim Albery further confuses the story by adding his own abrupt and implausible ending.

This isn’t to say Don Carlo is bad. It’s quite nice by the standards of conventional opera, if not those of conventional morality or good taste. Verdi’s opera was a flop when it opened; originally clocking in at four hours and including a ballet, critics judged it too long. Verdi agreed and cut it considerably. But it went on to a central place in the canon for its dramatic music, particularly duets between conflicting characters. Philippe Auguin’s careful conducting captures all the suspense and anguish of Verdi’s composition, with ethereal presence by the strings and harp. His final opera as the company’s music director proves yet again WNO’s mistake in letting him go after his masterful handling of The Ring.

Auguin alone is worth the ticket, but there is solid singing all around from a cast of WNO’s best regulars. Playing the king is the always impressive Eric Owens, a sonorous bass-baritone who has anchored many of the company’s weightiest productions. Russell Thomas is capable in the title role, though often upstaged by his duet partner, Quinn Kelsey as the Marquis of Posa, with a high register, resonant baritone full of vibrato. As Queen Elisabeth, Leah Crocetto, a dominating soprano, is bright and clear, while standout mezzo Jamie Barton manages to inspire the most empathy in a clichéd woman-scorned role as Princess Eboli. And bass Andrea Silvestrelli is terrifically creepy as a hooded, Emperor Palpatine-like Grand Inquisitor.

Don Carlo is an expansive and expensive opera to put on, requiring a full orchestra and dozens of performers. It’s also still too long, even this whittled-down, four-act version. There are subplots that are unnecessary or never get resolved—a stock Orientalist side story about a Moorish king, a protracted dispute over Elisabeth’s servant which never gets mentioned again. Costume designer Constance Hoffman has a dark, stylish take on the period dress, though Andrew Lieberman’s sets simply continue WNO’s “giant hole in the wall” philosophy of stage design. Overall, it’s an impressive production that hits all the questionable marks Verdi set for it. Don Carlo is a spectacle for sure, albeit one that may make you a little queasy.

At the Kennedy Center Opera House to March 17. 2700 F St. NW. $45–$300. (202) 467-4600. kennedy-center.org.