The Passion, Port Talbot<br/>Cardenio, Swan, Stratford-upon-Avon<br/>Macbeth, Royal Shakespeare Theatre, Stratford-upon-Avon

Actor brings agony and ecstasy to his home town, while the 'new' Shakespeare appears dull-witted

Streaming sweat and blood, Michael Sheen is just inches from me, horrifyingly crowned with thorns.

Through the parting crowd, he's dragging a cross up Station Road towards the red-brick Civic Centre and the M4 – the hulking bypass that has led to Port Talbot's being overlooked (literally and metaphorically) for decades.

The Passion has to be the most extraordinary piece of community-specific theatre I've ever beheld: a radical reworking of the Jesus story which – albeit with agonies en route – uplifted Port Talboters over three sunbaked Easter days. Drawing thousands of excited spectators, it was also a personal homecoming as Sheen returned to the beach resort turned industrial conurbation where he grew up. He also co-directed this National Theatre Wales production, along with Bill Mitchell.

Its cast of professional actors and a thousand local amateurs pop up in the unlikeliest places: on the seafront; in an underpass abutting a graveyard. The drama really came together at the Last Supper, in a social club where The Manic Street Preachers were introduced as the house band and the crowd went wild. There followed a hallucinatory reimagining of Gethsemane, where Sheen – perched under a streetlamp on an earth-filled skip sprouting flowers – was encircled by hoodies on bikes with blazing wheels.

This Passion was, essentially, not religious. It was about raising the dejected spirits of Port Talbot. Sheen's Teacher is an ordinary bloke-turned-missing person. Scruffy and hirsute, he shuns material possessions, and gains a following for his ability to comfort distraught outcasts – assuring them that they're not dead, that he can see them and is listening.

He steps in at the seafront first, to soothe a female suicide bomber who's been accosted by gun-toting security guards protecting the Company Man (Hywel Simons), a dictator ripping through the town to mine minerals. The Company Man decides the Teacher is a dangerous rallying point for protesters, and puts him on trial.

Purely as theatre, one might have hoped for better. At first, I struggled to work out what was going on, squinting through a forest of cameraphones. There were delays, and it was only thanks to Twitter that you gleaned that Sheen had earlier spent a night, in character, on a nearby hillside. Yet such shortcomings mattered little. The sun shone, the beach was glorious, and Sheen – standing on a graveyard wall before his arrest – exuded beatific serenity.

The people of Port Talbot displayed a sunny disposition too, lauding Sheen not only as a neo-socialist hero but also a man who – by listening to local memories – was reviving Port Talbot's sense of self. His final, epiphanic moment was fantastically bold and poignant. Crucified on the prom, he cried out, "I remember, I remember!" followed by Last Words that were a rainbow of local reminiscence – "the smell of slaughterhouses on Water Street", the name of a long-lost sweet shop – a litany greeted by cheers and nostalgic laughter. Transcendent.

"This good old master is, by a kind of miracle, recalled from the grave." So claimed the 1720s advert for The Double Falsehood, aka Cardenio. Now the RSC has resurrected what it describes as "Shakespeare's 'lost play' re-imagined". Cardenio's authorship is certainly debatable. It was presented in 1727 as a rediscovered gem by Shakespeare, but even then some deemed it a fake. It may have been a version of an earlier adaptation of a 1612 Shakespeare-Fletcher collaboration, itself inspired by Don Quixote.

In a dull-witted production, this tale of lovers parted, duplicity and pastoral cross-dressing at times seems a B-rate imitation. But what's thrilling about Gregory Doran's intimate Swan staging is how his actors find humour and nuance in exchanges that look flat on the page. No scene leaps out as unquestionably Shakespeare, but I buy the Fletcher theory after this rendition. Any 18th-century add-ons are certainly well concealed. Doran has added new bits of his own – including a startling near-rape and an abduction – that fill jolting gaps in Theobald's version.

Alas, the first major new production in the splendidly rebuilt Royal Shakespeare Theatre is a comparative dud. Michael Boyd's staging of Macbeth offers no startlingly inspired readings. Jonathan Slinger's regicide is a grinning death's-head, and neither he nor Aislin McGuckin's Lady Macbeth are emotionally gripping. Yet still Boyd tightens the satanic snare. Slinger is shadowed by his sardonic devil-porter, Seyton (Jamie Beamish), and child-ghouls double as witches and Macduff's slaughtered babes: strung-up corpses twitching into life in a war-wrecked chapel.

'Cardenio' and 'Macbeth' (0844 800 1110), both to 6 October

Next Week:

Kate Bassett sees rising star Joshua McGuire tackle Hamlet at the Globe

Theatre Choice

In Mike Leigh's self-directed, slice-of-life Ecstasy (Duchess, West End, to 28 May), Sian Brooke boozes with friends in a bedsit. The Interminable Suicide of Gregory Church, storyteller Daniel Kitson's curious saga about an attic full of morose letters, goes to Brighton Pavilion (Wed & Thu), Durham Gala (Fri) and Sheffield Crucible (Sat).