It has already been announced that Chichester’s summer production of Singin’ in the Rain is heading to the West End’s Palace Theatre in the new year, promising to brighten the dark winter nights with cheerful fun. But now they’ve brought this year’s season to a boldly terrifying end with an utterly chilling, thrilling production of Sondheim’s brooding musical masterpiece Sweeney Todd that is as dark and uncomfortable as I’ve ever seen it.

At once grim and gripping, Jonathan Kent mines Sondheim’s musicalisation of this story for an operatic grandeur that reveals it in all of its epic intensity, yet also anchors the series of domestic tragedies that play out within it.

It’s the story of a man, after all, who returns to England from being exiled to Australia on a false charge, only to find his family destroyed by the judge who sentenced him, and vows revenge as a result. Meanwhile, the lonely but forever pragmatic Mrs Lovett has other agendas - both to claim him for herself, and establish a thriving business for them both.

This staging, which thrusts a Victorian tale into an unspecified 20th century era, is galvanised by two stupendous performances. Imelda Staunton is the expected comic and yet also tragic triumph as Mrs Lovett, lending her both wit and grit. But Michael Ball is an unexpected revelation, not just because he is virtually unrecognisable - only his trademark dimples give him away - but because he dares to appear so relentlessly unsympathetic. Of course, he also brought unusual depth - not to mention width - to Edna Turnblad in Hairspray, but here he is operating in another dimension entirely, and sings Sweeney’s fierce, passionate songs like arias, with a voice from the gods but a heart cast in stone. Both Staunton and Ball are also remarkable for the utter clarity with which every lyric can be heard.

But then there’s not a weak link in an astonishing cast that also includes richly sung and acted performances from Lucy May Barker’s Johanna, Peter Polycarpou’s Beadle Bamford, John Bowe’s Judge Turpin, and James McConville’s slight, vulnerable Tobias.

Mark Henderson’s lighting casts dark shadows and harsh spotlights on Anthony Ward’s spectacular industrial set that brings a piercing darkness to this most arresting and insinuatingly creepy of all modern musicals.