Overlooking the park is a theatre, whose auditorium you reach via a series of rooms containing simple furniture and gigantic tiled stoves; the fading wallpaper is hand-painted, and the whole place has a lovingly carpentered feel. But the stage, with its receding vistas of painted wooden foliage and its solid wooden waves, seems familiar. Wasn't this the setting for Ingmar Bergman's Magic Flute? Wasn't it also the trysting-place for Nolte and Scacchi in Jefferson in Paris?
Actually, no. Those films were shot in carefully mocked-up replicas: Drottningholm Court Theatre has been preserved in its original 18th-century state like a fly in amber, and is far too precious for film crews to be let loose in it. Also, the theatre is highly combustible and smoking here is a capital crime. The staff still recall with horror the moment when Princess Margaret casually lit up while on a backstage tour: the cigarette was angrily snatched from her fingers. In the wooden labyrinth below, and the ship-like rigging above, even flash photography is forbidden.
The sets move in and out of view through a system of ropes and pulleys operated by a giant capstan requiring four men to turn it. In the flies are the painted wooden clouds on which the deus ex machina descends - as he often does in Baroque opera - to sort out the mess the humans have made. A handle turns the wind-machine, while the rope-operated thunder- box consists of a large coffin filled with pebbles: both make a very convincing noise.
Together with the palace and its adjoining Chinese pavilion, the theatre is a Unesco-designated world heritage site, and the Swedish government monitors its activities closely. Ideally, it would like to mothball it completely, a proposal that its director, the soprano Elisabeth Soderstrom, has successfully fended off with a compromise solution permitting 50 performances a year.
Yet the theatre only survives because it was mothballed for 100 years. It was built for the pleasure of King Gustavus III, and its perspectives reflect this, converging on two big armchairs in the front of the stalls. His assassination in his public theatre in Stockholm - the real-life event on which Verdi based his opera Un ballo in maschera - was the signal for this private theatre to be permanently closed as a mark of mourning. From 1792 until 1922 it was used as a billet for troops and a romper-room for royal children. But the Swedes never throw anything away: when the props and sets had been dusted off by an enthusiastic theatre historian, they recognised the treasure they had been sitting on.
Soderstrom, who made her operatic debut on these same boards in 1947, has developed a policy of reviving neglected works from the time of Mozart and Gluck. For years she's had her eye on Tom Jones, a racy opera-comique by Francois-Andre Danican Philidor which was last staged in Drottningholm as part of the aesthete-king's betrothal celebrations in 1766.
Fielding's novel, with its convivial dissoluteness, was all the rage in mid-18th century Paris. And Philidor himself was a double celebrity, combining musical eminence with world-wide fame as a grand master at chess, a game he learnt while a page at the Chapelle Royale (where cards were forbidden). His biggest stunt, which he did for Frederick the Great at the Chess Club in London, was to take on, blindfold, several challengers at once. His most acclaimed work was not an opera, but his much-reprinted L'analyse des Echecs.
But Tom Jones does boast the first septet in operatic history, and while none of its arias could make it into the big league, the scoring is inventive, the music full of Mozartian sparkle. For this revival, Soderstrom has hired the Royal Opera House's stage director John Cox and, as music director, Nicholas McGegan, who first exhumed the work in 1972. With the versatile Paul Brown as designer, and a largely British cast (singing in English), we arrive at a piquant recipe: a slice of English life, seen through French eyes, and presented in Sweden.
No designer starts here with a blank canvas. Taking his cue from the surrounding fait accompli, Brown has devised discreet additions to the standard sets for drawing-room and garden which contribute an extra comic frisson. The foliage now sprouting from the ground underlines how closely 18th-century conventions prefigure 20th-century stylisation. On the other hand, Brown's design for the tavern scene seems strange - long benches more suggestive of a Presbyterian chapel - and his anachronistically bright reds jar with the soft colours linking the stage with the painted stucco of the auditorium.
The 24-piece orchestra, sporting perukes and playing period instruments, really make the building sing, and with Brian Burrows bringing larger- than-life energy to the role of Squire Western, the pure-toned Judith Howarth as his headstrong daughter and the improbably handsome Greg Fedderly as the hero, the production has plenty of oomph. This is not a piece for virtuosity - the music loyally serves the drama, and its vocal demands are modest. But when Burrows and Howarth sing their sulphurously angry duet, or Fedderly sings of his desolation at being ousted by the ill- favoured Blifil (sung with rather too much charisma by Gordon Wilson), the music takes wing.
But this isn't Mozart, as we are reminded at the denouement, which here means exactly that: a granny knot of intrigue, breathlessly unravelled (in speech) by each player in turn. Setting this to music was in 1765 a challenge to which not even the world's grandmaster dared aspire. And it seems a shame McGegan couldn't have taken a small liberty with the libretto - at the start of Act 3, say, as the characters complain of a storm outside - to show what the thunder-machine can do, or drop a wooden cloud.
The intervals here are short and sweet, as punters share the park with swans and flying geese. There's no whiff of Glyndebourne-style exclusiveness, and the top seats cost only a third of their counterparts at Covent Garden: just as you'd expect, in Social-Democratic Sweden. Next summer, as a result of a budget cut at Stockholm's main opera house, there's an opportunity in Drottningholm which some other British company might capitalise on: 15 vacant dates, currently up for grabs. Go for it now, I'd say.
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