Twelfth Night, NT Cottesloe, London<br/>Tiger Country, Hampstead, London<br/>The Knowledge, Bush, London

Peter Hall's return to the National Theatre to direct his daughter Rebecca as Viola is a sad disappointment

Sticklers will observe the timing. Had Sir Peter Hall's NT staging of Twelfth Night – starring his daughter Rebecca Hall – got its skates on, it could have opened, as per its title, on the last day of Christmas.

But hey ho, Shakespeare's comedy, subtitled "What You Will", transports us to a realm that allows somewhat more leeway than usual.

In Illyria, where the shipwrecked Viola washes ashore and disguises herself as a boy, the fluidity of the seasons, like the switching of sexual identities, can seem like a dream. The locals allude to midsummer madness and May mornings, as well as inclement wind and rain. Anthony Ward's design for this production looks principally autumnal, with dead leaves scattered at the foot of a sea wall, below a twee miniature townscape. Perhaps that suits the melancholy opening scenes, where Rebecca Hall's Viola laments her twin brother – supposed drowned – and Marton Csokas's Duke Orsino hammily calls for music with "a dying fall". He's lovesick for Amanda Drew's bereaved Olivia.

The trouble is this production, from thereon in, seems energy-sapped and slow, and it's the comic timing that's poor. The Elizabethan costumes may embrace some sunnier hues, Olivia's eventual wedding gown being tangerine silk, yet there are no brilliant directorial epiphanies. This is a great shame because Twelfth Night was meant to be a celebratory return for Sir Peter, now 80, to the South Bank powerhouse that he opened in 1973 and ran for 15 years (after founding the RSC, as a wunderkind, in 1960).

Rebecca Hall is a fast-rising luminary, deservedly too. She beautifully conveys Viola's blended sorrow and resilience. With gentle smiles, she's understanding when Olivia falls for her masculine attire. However, she never really looks borderline male, and the play's fascinating layers of hetero- and homosexual attraction aren't fully explored.

Charles Edwards generates droll moments as the prancing twerp Andrew Aguecheek, and Simon Paisley Day's Malvolio strikingly plays up the social climbing element. However, Simon Callow's drunken Sir Toby is a wearisome, booming cartoon, mouth twisted to one side like Popeye. And even if Twelfth Night is concerned with the point where fun and japes turn sour, David Ryall's perfunctory, Feste is dismal. When he tried to instigate an audience singalong on opening night, only a few wan voices chorused "The rain it raineth every day", like a ward of depressives with seasonal affective disorder.

In Tiger Country, Nina Raine's new play set in an NHS hospital, some of the medics are so overworked and stressed by the competitive hierarchy that they're making themselves ill. Ruth Everett's Emily, a new senior house officer, cares too intensely. Her more experienced colleagues appall her, with their flippant jokes about terminal cases and refusal to race between cardiac emergencies or to bend bureaucratic rules to save lives.

Given the surfeit of TV hospital dramas, one might wonder if we need another on stage, and Raine doesn't entirely avoid the formulaic. That said, her self-directed premiere is full of insights both alarming and heart-wrenching. Her traverse staging – on a wide, blue stage – alternates fluidly between hectic crises and hushed scenes. The acting is superb, especially Thusitha Jayasundera's registrar who feels she has to be super-brusque to manage her team. And Adam James is such a natural with a stethoscope that – trust me – it's hard to believe he's not a real doctor.

Meanwhile, state education comes under scrutiny in the Bush Theatre's Schools Season, starting with The Knowledge by John Donnelly. Joanne Froggatt's Zoe, a new teacher, undergoes a baptism of fire at a failing comp, struggling to endear herself to the "retards' class" of hair-raisingly insolent delinquents.

Charlotte Gwinner's in-the-round production instantly draws you in, being horribly funny and promisingly tense. Andrew Woodall is superb as the sardonic head. Christopher Simpson has a dangerous glint in his eye as Zoe's skirt-chasing colleague. Among the pupils, Joe Cole is destructive stupidity incarnate, his slack-jawed, steely-eyed Mickey wrecking Zoe's lessons with the cold belligerence of a tank. Kerron Darby's Daniel is more cleverly manipulative – or needy. Unfortunately, Froggatt doesn't quite capture the ex-bad-girl side of Zoe. Plot developments involving racial tension and sexual impropriety, are also underdeveloped, and perhaps too indebted to Skins, Teachers, and Notes from a Scandal.

'Twelfth Night' (020-7452 3000) to 2 Mar; 'Tiger Country' (020-7722 9301) to 5 Feb; 'The Knowledge' (020-8743 5050) to 19 Feb

Next Week:

Kate Bassett hastens to Shakespeare's "long lost" play, Double Falsehood

Theatre Choice

Director Lucy Bailey's gripping rendition of Roman politics in the RSC's transfer of Julius Caesar. Greg Hicks is the doomed emperor (at London's Roundhouse to 5 Feb). Meanwhile, The Arcola Theatre has moved to a Victorian factory in Dalston, east london, kicking off with Rebecca Lenkiewicz's intimate biodrama The Painter (to 12 Feb).