The Prince of Homburg, The Swan, Stratford-Upon-Avon;<br></br> I Can't Wake Up, Lyric Hammersmith, London;<br></br>The Homecoming, Royal Exchange, Manchester

Born-again Romantics are having a field-day. Even as the "New" variety flock to Boy George's musical, Taboo, aficionados of vintage German Romanticism are dashing towards Stratford to catch The Prince of Homburg, directed by Neil Bartlett. The titular, near-tragic hero of Heinrich von Kleist's 1809 drama is a youthful dreamer who – with echoes of Hamlet – is out of line in regimented Prussia. During the opening scene, he sleepwalks in the Elector's castle gardens. Unconscious of surveillance, he's weaving a laurel garland when he should be with his troops. He's distracted from listening to orders by the loveliness of the Elector's niece. Then having led an unscheduled charge against the Swedish foe, he faces a court martial and a moral dilemma – either pleading for mercy or boldly choosing death.

I'm not persuaded this is a neglected masterpiece, but Bartlett tackles tricky classics with intelligence and bravura. The minimalism of this staging is visually stunning (designed by Rae Smith), with the ornamental gardens pared down to a black slope where our wreath-bearer perches by a patch of loose earth. Evoking weird Symbolist paintings, Bartlett recognises that Kleist was, in fact, an experimental Romantic-going-on-Modernist.

Battle scenes, meanwhile, combine the nitty-gritty of strategy meetings with an impressionistic, slow raising of swords. The production ensures the Prince's final "happy" salvation is ambivalent – reflecting Kleist's own love-hate relationship with the establishment. And generally, the cast's contained acting style (helped by a taut new translation) counters Kleist's flowery, neo-Shakespearean imagery. However, the rigour goes too far. Dan Fredenburgh's Prince is too static and stolid for an impetuous youth. James Laurenson's Elector is, more intriguingly, mellow yet icy underneath and Will Keen – playing the Prince's devoted companion, Hohenzollern – steals the show with his riveting mix of dry propriety and suppressed passion.

It's auf Wiedersehen to unorthodox calvary officers and hallo to demented naval commanders in I Can't Wake Up. In Told By An Idiot's latest piece of tragi-comic clowning – partly based on John Toohey's book, HMS Portable Nightmare – Captain William Mallen looks shipshape but goofy. Embodied by Paul Hunter, he's a bug-eyed chap in a bicorne hat that's almost as wide as he is tall.

We catch glimpses of William's life on the ocean, (supposedly) penning letters, handing out rations and scanning the horizon to get his bearings. But actually he has lost his mind and is in a dream-world back at home, nursed by his wife, Emily (petite Catherine Marmier), and a doctor (stringy Richard Clews).

What's absorbing is we're made to view the world madly ourselves. A vast sail hangs from a wonky mast and an off-kilter oak table shoots through an incision in the canvas. The story-telling is deliberately "out of order". Flashbacks, fantasies and Mallen's present reality – including wacky modern-day touches – swirl and overlap.

All this celebrates the unleashed imagination. There's delightful inventiveness as Hunter swings a cognac bottle up to his eye, serving for a telescope, or as Marmier and Clews quarrel – not verbally fulminating but blasting each other like hurricane force winds. On a more sombre note, I Can't Wake Up suggests madness is a weapon which can subjugate those who care for the unstable. Emily and the doctor are symbolically "at sea", swaying with exhaustion.

This piece does not depict mental illness with great medical accuracy, and Hunter milks several big speeches. But as their 10th anniversary approaches, Told By An Idiot are still a joy. Marmier is dignified and flamboyantly ridiculous by turns. Clews's ad-libbing wittily combines the ornate and the inarticulate. And director John Wright engineers a curiously brilliant ending. William's body, on his deathbed, is replaced by his miniature writing desk – its wooden lid breathing his last – and Hunter and Marmier materialise on a promontory, serenely gazing out to the strains of the rock group Slade chorusing, "And I don't know why" (from "Cum On Feel The Noize"). Ludicrous and irrationally transcendent.

The menace of brutality ought to ensure The Homecoming packs a punch. In Pinter's mid-1960s classic, the academic Teddy returns to his East End roots to receive a deeply screwed-up welcome from his father and pugilistic brothers who move in on his alluring wife, Ruth.

However, Greg Hersov directs a low-impact revival. Laurie Dennett's set, with its baize green carpet, does imply this household is akin to a nasty gents' club, and Hersov hints at dark fantasies as the men stand wreathed in cigar smoke. Yet Paul Hilton's Lenny is better at exposing flashes of vulnerability than turning vicious, while Simone Lahbib's Ruth has insufficient magnetism. As Max, Pete Postlethwaite is horribly seedy at points but, scuttling around in a cloth cap and pyjamas, he mainly brings out the comedy in Pinter's writing. There are also some awkward sniggers as, without sharp acting, the mounting degeneracy just looks preposterous. Bantamweight, at best.

k.bassett@independent.co.uk

'The Prince of Homburg': Swan, Stratford-upon-Avon (01789 403403), to 16 Feb then Lyric Hammersmith, London W6 (020 8741 2311), to 30 March; 'I Can't Wake Up': Lyric H'smith (as above), to Sat; 'The Homecoming': Royal Exchange, Manchester (0161 833 9833), to 2 March