Mozart wrote the opera seria Mitridate at the age of fifteen. The Bayerische Staatsoper’s clever and strangely beautiful production positions it as the work of a child, full of rebellious teenagers and projected scenery seemingly drawn from a primary school art class. But unfortunately even excellent singing and much directorial invention cannot disguise that this is a rather bland opera, and its four hours pass slowly.

The plot concerns dynastic drama in the kingdom of Pontus. The king, Mitridate, is believed to have been killed by the Romans, leading to his sons Sifare (good) and Farnace (bad, aligned with the Romans) fighting it out for the kingdom and his fiancée Aspasia (who loves Sifare). But he is not, as it turns out, dead, and once he returns things get even more complicated. Despite the very eventful plot, however, the music unfolds in generic fashion. The arias are brilliant, virtuosic, and often on their own terms fun listening. (Several are popular as concert pieces.) But they don’t do much to develop the characters or the drama, and this sameness, exacerbated by the near total lack of ensembles, makes the opera a bit of a slog.

Director David Bösch has set the opera in a mythic world as envisioned by a contemporary child, with the characters washing up on the island setting in an inflatable raft. Sifare is a schoolboy while Farnace is a teenage thug, and Aspasia a naïve teenager in rubber rain boots. Mitridate, when he shows up, turns out to be a father both scary and ineffectual, armed to the teeth and prone to rash action. While Act I was mostly fun and games, the violence in Acts II and III is all too real. The dark, mostly empty stage has a curved backdrop (something like an IMAX screen) that serves as a screen for set designer Patrick Bannwart’s charming projections of birds, waves, and other simple images, all in the style of a child’s drawing. A large chandelier also appears for no reason in particular, suggesting the absent dynastic palace and also giving Mitridate something to swing on. The visuals are strikingly beautiful and unique, and the action is, in Munich’s small Prinzregententheater, intimate and direct.

Bösch’s strategy to move the characters from childish infatuation to reality to maturity—and, in Farnace’s case, forgiveness—gives the opera some shape. But while it makes neat work of the plot’s filial conflict and mysterious violence, it also has drawbacks. Mitridate might be the work of a child (and the production relies implicitly on Mozart’s biography, father conflicts and all), but it’s also a typical opera seria, with outsized passions and violence. The music’s most notable feature is its brilliant drive and poise. Bösch doesn’t stint on the blood, but as told by a group of adolescents the passion and grandeur is sometimes lacking, particularly from Aspasia (Farnace and his forgotten bride Ismene fare much better). While Bösch knows how to keep the stage action moving through the endless sequence of arias, on occasion the arias still feel endless.

The cast was, on the whole, excellent, and made singing this very difficult music look easy. Most of them appeared in the premiere run of this production last year, and acted with uniform commitment and intensity. Barry Banks sang the title role with great strength and spontaneity, even though his nasal, bleating tenor is not the most pleasant sound. Anna Bonitatibus’ fruity mezzo sounds low for Sifare and her phrasing sometimes involved too many gasps and scoops, but her flair and bravura are great fun. Lawrence Zazzo as Farnace played the hothead with manic brio in Act I but in Act II turned dangerous and suicidal. He was unafraid to mine the register breaks in his big but reedy countertenor for comic effect, sometimes going into the baritone register.

Anja-Nina Bahrmann sang Aspasia’s daunting coloratura writing with impressive accuracy and consistency, though her bright metallic tone is not the most ingratiating. Lisette Oropesa as Isemene sang with the most beautiful sound in the cast, her soprano light but luminous, but her coloratura doesn’t quite sparkle. In the smaller roles, Eri Nakamura made a perky sidekick to Sifare, and as Farnace’s Roman sidekick, Taylor Stayton’s Mozart tenor made you wish that he sang a little more.

Mark Wiggelsworth conducted a contingent of the Bayerisches Staatsorchester (the balance of whom were playing La Bohème in the Nationaltheater at the same time) with energy and verve. Zoltán Mácsai contributed a remarkably polished and gracefully phrased solo on the natural horn in Sifare’s aria “Lungi da te.”

While this is a lovely production with many accomplished performances, it still somehow doesn’t take off, and for that the opera itself is mostly to blame.