THEATRE / Showdown at Avebury Manor: Summer-time, and the theatre is breezy, as the grounds of stately homes are opened to touring companies. Ellen Cranitch on the picnic and play set

It was a quintessentially English summer scene: around me the audience were lounging on rugs with hampers and bottles of fizz; before us Showdown Theatre Company, cleavaged and crinolined, performed Goldsmith's She Stoops to Conquer on the striped lawn of Avebury Manor, a National Trust country house in Wiltshire. It was Midsummer's Day and it was raining. Golf umbrellas sprouted; families unpacked picnics and anoraks with gritted cheerfulness; the damp rose inch by transfixing inch on Kate Hardcastle's pink frock.

There's a stoicism verging on the eccentric in the audience for these events, and something peculiarly English about the way they behave as though they are not wet, as though there are no low-flying aircraft manoeuvring precariously close to the manor house, as though there are no latter-day druids gathered a stone's throw away, ululating mournfully in the direction of the rising sun.

Showdown consists of an intrepid mother and son team, Barbara and Mace Richards. She directs, he acts and produces. In the summer their ranks swell, this year's cast numbers 11 and includes their long-term collaborator Jonathan Stafford. A different brand of English eccentricity courses through the Richards family's veins - an unalloyed passion for drama, in all its forms, with all its problems. Grand-uncle was a film actor in the Thirties, playing alongside Charles Laughton. Barbara's husband does PR for Rank films.

Showdown is based at Barbara's cottage in Epsom, where theatreflyers litter the kitchen and props sabotage you from behind the doors. Barbara, in tireless middle-age, speaks rapidly and nervously; she worries, enthuses and jokes all at the same time. Sometimes she wonders why she keeps going; to finance the company she and the core members have had to dig deep into their pockets. Box-office receipts ( pounds 6-8 per ticket) don't suffice. This year, though, a substantial grant from the Foundation for Sports and the Arts has helped considerably.

Negotiating with the National Trust also has its headaches; next year she wants to do The Lion in Winter, but the NT fears it's a bit heavyweight. Mace, the eldest of her three sons, recalls that he laid out his career aims at the age of four. He wanted to be an actor, a dustman and the Queen.

Now, adept at character parts and juvenile leads, and with a spell in refuse behind him, he has fulfilled the majority of his ambitions. His brothers, he confides, - one a chef, the other an employee of British Rail - think he and their mother are mad.

The presence of ancient stone circles at Avebury next to the Manor House is just one of the hazards Showdown has to contend with tonight; since travellers were banned from Stonehenge, they turn out in force at Avebury to celebrate the summer solstice. As Barbara describes the characteristics of the other venues, you begin to see why the very title of her company smacks of the apocalyptic. Apart from the eternal unpredictability of the elements, to say nothing of the unsolicited participation of cats, dogs, mice and peacocks, there are specific complications peculiar to each site.

Arreton Manor on the Isle of Wight is big on Living History - locals dress up as Roundheads and Cavaliers and enact the English Civil War. Here, there's the perennial danger that some of the Living Historians will wind up in a scene from She Stoops to Conquer, their costumes clashing magnificiently with the Restoration dress of Goldsmith's comedy.

Showdown also has to liaise with the aristocratic families which occupy part or all of the houses they tour to. These are the sort of eccentrics whom Barbara characterises as 'terribly nice but rather vague and elderly'. Dealing with the Arts Council is one thing, dealing with the heir to the Scottish throne (Lord Fitzwalter, present incumbent of the venue Goodnestone Park in Kent, can make some claim to that title) is quite another.

And it's not just the weather that's unpredictable. During a performance of The Importance of Being Earnest two years ago, Showdown used the front door of Stanstead Park, Hampshire, as part of their set. The cast was amazed when a stage knock was answered from within. The redoubtable Lord Beuborough had forgotten that there was a performance on and assumed it was a visitor for him.

The performances at Avebury Manor tonight are erratic but the direction is assured and the mullioned windows of the house, just perceptible through the drizzle and over the umbrellas, do look rather lovely. While some of the audience look like they are in danger of terminal pneumonia, others have desensitised themselves with alcohol. Though the costumes are waterlogged and an unruly wind has threatened the fabric of the set, Goldsmith's play appears to have infiltrated peoples' imaginations. There's warm applause as it ends.

After the performance, the soaked cast cram into the Red Lion pub, set in incongruous isolation in the middle of the standing stones. Barbara, devouring a packet of cheese and onion crisps, is wondering out loud, yet again, why she doesn't give up. Mace downs a pint of Speckled Hen and buoys her up, his optimism rising as his glass drains.

Showdown's tour of 'She Stoops to Conquer' continues at Arreton Manor, Arreton, Isle of Wight, tonight (0983 528134); Kingston Lacy, near Wimbourne, Dorset, on 7 and 8 July (0202 880413) and at Borde Hill Garden, Haywards Heath, West Sussex on 9 and 10 July (0444 441102)

(Photographs omitted)