FRINGE / Living off the fat of the land: Sarah Hemming on Fat Souls and Lardo Weeping, plus the RSC's A Jovial Crew

TUBBY, or not tubby: fat is the question at two fringe theatres this week, as attitudes to obesity come under scrutiny. Plumpness even creeps into the title of James Martin Charlton's Fat Souls, whose ample protagonist goes by the name of Fat Mags, while in Terry Galloway's solo show, Lardo Weeping, we see America from the point of view of a large lady called Dinah LaFarge. Both women are vulnerable, lonely and endearing, and in both plays their plight emphasises the callousness of the society they live in.

In Charlton's play, Fat Mags has more than size stacked against her. She's been on the dole since leaving school, a shy teenager without family, friends or prospects. An interview for a job as office dogsbody glistens before her as an opportunity to find friends - perhaps even love. The office staff, however, prove a callous, selfish lot, who mock Mags for her size; only the errand boy Lamb shows kindness to her. But Lamb's gentleness marks him out as a sacrifice to a jilted lover's rage.

It's a simple story, but a remarkable play. Charlton writes with energy and jauntiness, strapping ancient dramatic traditions to his modern tale with great success - the play is written in verse and the characters wear masks, yet this never appears forced or gauche (Charlton is well served in this by Ted Craig's confident, buoyant production). Charlton's depiction of the animal-like office staff is evocative of Jonson in its relish of stereotype, and you are busy enjoying these - the grasping minx of a secretary (Natalie Ogle), the office stud (James Arlon), the pimply camp-follower (Thomas Stephen Murphy) - when the import of the play's story and Lamb's sacrifice creep up on you. This is a play about the redemptive power of love with distinctly Christian undertones, yet it is never mawkish, rather it is funny, touching and enjoyably theatrical.

It is at its least successful when Lamb is teaching Mags to love herself and nature in his garden, employing lines like 'Hear the flap of a butterfly's wing' (which Daniel Matthews, as Lamb, manages remarkably well). Otherwise it reveals a refreshing and promising new voice, and is belted out by a strong cast, not least Joanna Brookes as the engaging, timorous Fat Mags.

Dinah LaFarge in Lardo Weeping has had no Lamb figure to coax her out of her refuge. When we meet her she is both literally and mentally barricaded in against a hostile world. She treats the audience as honoured yet suspicious guests, offering them a tour round her ramshackle kitchen and even more confused psyche.

Determinedly fat and unfashionable, she perceives herself as the deliberate antithesis of the ideal American woman. But her identity is clearly far from comfortable and as she begins to rip off her clothes, then a set of false breasts, her torment erupts. This is a strange, surreal piece from Terry Galloway, at times fascinating, at times plain weird. She is a compelling performer and the nightmarish quality of Dinah's existence stays with you, but the show dips too often and is half an hour too long.

Young homeless people roam the roads; fortunes can be lost in next to no time - yet this is not a new play by a contemporary writer, but Richard Brome's 17th-century A Jovial Crew, which, in Max Stafford- Clark's excellent, boisterous production, has joined the RSC's Barbican repertoire in London - where it seems even more to the point than in Stratford. Brome's portrait of a fluctuating society, and the beggars who choose a life of flux alongside it, is wittily adapted by Stephen Jeffreys to be accessible while retaining its character.

The play tells of a landowner's two daughters who, bored with their lot and enchanted by the apparent insouciance of a roving group of vagrants, decide to join them, dragging along their hapless swains. Add assorted runaway lovers and you soon have a curious new breed of beggar: 'Troubled times indeed when the mendicants plead in rhyming heptameters,' remarks one character. The production bowls along, revelling in the play's mischievous mood while clearly stating its serious messages, and a superb cast is led by Ron Cook's charismatic steward- turned-beggar. Book now.

'Fat Souls' runs to 30 May at Croydon Warehouse (081-680 4060); 'Lardo Weeping' runs to 29 May at the Finborough Arms, London SW10 (071-373 3842); 'A Jovial Crew' is in rep at the Pit, Barbican EC1 (071-638 8891)