One Flew Over the Cuckoo's Nest/Fatboy/Taking Charlie/David Benson's Haunted House, Assembly<br/>Gone/How To Act Around Cops, Pleasance<br/>The Karaoke Show, Gilded Balloon<br/>Ubu Disco, Smirnoff Underbelly<br/>Punch and Judy, Pod Deco

Recently in Edinburgh, everyone's been driven mad by the star-studded asylum play, One Flew Over the Cuckoo's Nest - or rather by the offstage dramas. Firstly, the director upped and left. Then opening night was further delayed when Christian Slater (in the Jack Nicholson role) fell ill. Hitherto, Slater has been known for playing big-screen bad boys and serving a jail sentence. Now, poor fellow, he has gone down in medical history as an extraordinary case of ornithological confusion. Instead of just acting cuckoo, he contracted chicken pox.

Recently in Edinburgh, everyone's been driven mad by the star-studded asylum play, One Flew Over the Cuckoo's Nest - or rather by the offstage dramas. Firstly, the director upped and left. Then opening night was further delayed when Christian Slater (in the Jack Nicholson role) fell ill. Hitherto, Slater has been known for playing big-screen bad boys and serving a jail sentence. Now, poor fellow, he has gone down in medical history as an extraordinary case of ornithological confusion. Instead of just acting cuckoo, he contracted chicken pox.

Last week, happily, the show was well enough to receive visitors. You'd hardly guess Slater was sickly at all. His McMurphy has plenty of pushy charisma, swaggering into Nurse Ratched's regimented ward and encouraging his cowed fellow psychopaths to question her no-fun regime. It's an assured performance but, rather surprisingly, lacks a dangerous edge. Several other parts are played by comedians. Phil Nichol enjoys himself as the leery saddo, Cheswick, but Owen O'Neill's uptight Harding is not convincingly explosive. Mackenzie Crook (from The Office) is more compelling as the stammering, hunched Billy, but doesn't seem quite desperate enough for his violent end.

This production should be stronger by September, with director Terry Johnson scheduled to tweak it into shape for its West End transfer. In the meantime, Frances Barber steals the show: an icily smiling Ratched with a mask-like powdered face and darting eyes. Dale Wasserman's dramatisation (based on Ken Kesey's novel) is obtrusively didactic. Nonetheless, it's a sound political allegory, advocating active protests against dictatorial regimes, including those that claim to be democratic.

David Benson isn't batty but he may be hallucinating in Haunted House, a less star-struck piece of storytelling than his previous hit impersonations of Kenneth Williams et al. In this one-man show he fondly reminisces about his superstitious grandpa, re-enacting the spooky bedtime yarns he used to spin (including one nicked from M R James). In a grimmer mood, Benson confesses to visions of a morbid figure waiting in the shadows. The ghost stories are engrossing, and he is enjoyable company. However, the gothic climax fails, being neither genuinely scary nor a comic scream.

Sam Mendes' new production company, Scamp, evidently reckons it can profit by embracing dumbed-down culture. Scripted by Jonathan Harvey, Taking Charlie is a lazily stereotypical, soapy comic monologue about a disappointed woman, padded with ill-amplified, satirically feeble and soppy songs.

Now, the Ubu fad. Alfred Jarry's vintage, shockingly brutal anti-hero is making a comeback. Written and directed by John Clancy (of American Absurdum fame), Fatboy is a grotesque, pseudo-Victorian panto. Mike McShane, in the title role, is half-Ubu and half-Mr Punch, stomping round like a jack-booted clown, bludgeoning anybody annoying. The satire ain't subtle when he starts talking like a US general, but the stylised acting is skilful. Ubu Disco - Jarry's tale of carnage with karaoke numbers slung in - has anarchic silliness but no political bite.

Meanwhile, Punch and Judy is a macabre multimedia cabaret by the Tiger Lillies, the punk-folk band from Shockheaded Peter. Martyn Jacques shuffles round like a Grand Guignol jester, screeching hateful lyrics. His talents as an actor are limited and the storyline is scrambled. Still, the projected puppetry is sometimes compulsive viewing and, even if the music is repetitive, the mix of nursery tunes, the blues, and Jacques's freakily high, floating voice is electrifying. The Karaoke Show is more fun and technically tighter, playing out the plot of Shakespeare's Comedy of Errors in an actual bar where the talented, flamboyantly kitsch cast chase through the crowd. The interpolated disco hits fit the characters' confusions but the karaoke format wears thin and it is less inspired than The Donkey Show, the same gang's carnivalesque clubbers' version of A Midsummer Night's Dream.

Half-farce, half-thriller, How To Act Around Cops is a taut, witty fringe hit from New York. The multiple plot twists are not always credible, but co-authors Logan Brown and Matthew Benjamin are surely Hollywood-bound. Also at the Pleasance, Glyn Cannon's Gone is a politically barbed - albeit sometimes strained - modernisation of Sophocles' Antigone with Nigel Hastings as a sharp-suited, suave Creon who justifies war with oratorical phrases that echo Blair and Bush.

In the International Festival, the radical reworking of Racine's Andromache is superb. Director Luk Perceval's five-strong ensemble - from Berlin's Schaubühne Am Lehniner Platz - look like a Greek frieze, perched on a high, narrow wall of funereal granite slabs. Forever trapped in a chain of unrequited love, Orestes reaches for Hermione, who clings to Pyrrhus, who turns to Jutta Lampe's Andromache. She stares out into nothingness, mourning Hector and the devastation of Troy. All around them is a sea of glittering, broken glass. This is a breathtaking, almost distractingly dangerous performance. Yvon Jansen's desperate Hermione is held aloft by Mark Waschke's sinuous Pyrrhus. Smashed bottles are held inches from throats and wrists. All this is, at the same time, done sparingly. The rewritten dialogue (in German with English subtitles) is a long way from Racine's flowing verses, but has a stark intensity that's true to the original. It also reverberates - for Germany and the wider modern world - as the war-traumatised Andromache asks why the Greeks so fear her race that they want to kill her child. What a shame this only ran for three nights at the Lyceum.

Fernando de Rojas' Spanish classic, Celestina, is more of a mixed bag, directed by the aggressively avant garde Calixto Bieito. Though pared to 30 per cent of its vast original length by English translator, John Clifford, this is a curiously rambling doomed romance. The young lovers are sidelined by the aged procuress, Celestina, who weaves spells to ensnare the lady. Not for the first time, Bieito's big conceit is to translate Renaissance tragedy to a contemporary mafiosi-style underworld of booze-glugging parties and murderous violence with, yes, interspersed disco routines. Sometimes his interpretation is far wide of the words, yet this can be fascinating, funny, and powerfully bleak. Kathryn Hunter is also magnetic. Her tiny, shorn Celestina - dressed like the Godfather - is hard as nails, sexually abusive and unexpectedly vulnerable.

'One Flew Over the Cuckoo's Nest', 'Fatboy', 'Taking Charlie' and 'David Benson's Haunted House': Assembly (0131 226 2428); 'Gone' and 'How To Act Around Cops': Pleasance (0131 556 6550); 'The Karaoke Show': Gilded Balloon (0131 668 1366), all to 30 Aug. 'Ubu Disco': Smirnoff Underbelly (0870 745 3085); 'Punch and Judy': Pod Deco (08707 557705), both to 29 Aug. 'Celestina': King's (0131 473 2000), to Tue