A naive young man falls victim to a corrupt judicial system, his family splinters and he wreaks a murderous, psychotic revenge on the society that spawned his desperate situation. Sweeney Todd, alas, is an uncomfortably relevant fable for our troubled era.

In the Ruins Courtyard of the Mill City Museum on Friday evening, Stephen Sondheim's musical played out amid the glowering casements and twisted stanchions of the Victorian flour factory, open to the darkening elements.

Central to Mill City Summer Opera's staging was a hut-like cylindrical construction, initially suggesting the ship ex-convict Sweeney debarks from in London, then flipping to the pie shop where Mrs. Lovett plies her trade, and the upstairs room where Sweeney harvests the human ingredients for her recipes. Hanging stage right was a cage from which a fresh-voiced Jeni Houser delivered Johanna's febrile "Green Finch and Linnet Bird," while on the left a giant pair of cutting shears swung upward as tenor Javier Abreu pinged his top notes feistily in Pirelli's shaving contest with Sweeney.

Vocally the show had plenty of highlights, not least mezzo Catherine Cook's contributions as Mrs. Lovett. She brought technical control and a lick of sensuality to "Wait," a tricky song to float effectively, and relished the ­climactic "A Little Priest," where the show's macabre mix of slapstick comedy and foul intent is at its most unsettling.

The dark side hollered balefully in soprano Emily Pulley's half-crazed Beggar Woman, and in the apocalyptic "City on Fire" sequence, where the hardworking ensemble singers morph into Sondheim's scuttling team of lunatics freed from Bedlam.

Sweeney himself was baritone Robert Orth, a haggard, careworn presence from the outset, whose tender, vulnerable rendition of "A Barber and his Wife" made clear why history continues to haunt him. Exactly where his slasher instincts come from isn't quite as obvious in director David Lefkowich's somewhat internalized conception of the character: This Sweeney boils within but never terrifies the audience with raw glimpses of his poisoned ideology.

A similar restraint informs Jake Gardner's firmly voiced Judge Turpin, whose momentary self-flagellation provides a rare clue to the sexual predations he is prone to.

The band, perched on a narrow scaffold platform, played punchily under the excellently paced direction of Brian DeMaris. They turned the screw effectively on Sondheim's sizzling music; on stage, despite powerful episodes, this was ultimately a "Sweeney" where the grip of evil never fully tightened.

Terry Blain is a Twin Cities-based classical music critic.