The handsome dining area keeps some cosy-pub virtues

The Leconfield, New Street, Petworth, West Sussex

The market town of Petworth is, basically, Antiques Central. You cannot move through its narrow streets without falling over a Queen Anne coal scuttle or Regency escritoire. If you have trouble sleeping in Petworth, just try to recall the names of all 35 antique shops that give the town its prevailing tone of expensive dinkiness. The Leconfield restaurant is itself a substantial antique.

For 250 years it was a pub called The Red Lion. More recently, it's been a car-hire joint and, inevitably, an antiques shop, but now it's been attractively hurtled back into the past. On the first floor there's a vast dining room, capacious as the warriors' mead-hall in Beowulf, with a vaulted ceiling, Georgian beams and traces of wattle and daub in the stairwell. It's so old, it wouldn't have surprised me if the waiters read out the specials in Anglo-Saxon.

The restaurant opened two years ago. It's big on fish dishes – head chef David Craig-Lewis used to run things at The Fish House in Chilgrove, where le tout Chichester used to head at weekends for his famed crustacea – the 'hand-picked crab with liquid wasabi and fennel wafers' was much talked-about, even if it was only to wonder about the phrase 'hand-picked', which is more generally used about footballers.

Anyway, fish is the thing in this handsome, solid-looking dining area, which keeps some cosy-pub virtues – the open fire, the exposed brickwork, the oak tables, the vodka martini… And there's a new arrival in the kitchen – Pascal Proyart, of the One-O-One restaurant in Knightsbridge. Pascal is from Brittany and loves game – within five minutes of our meeting, he was telling me proudly about the pheasant he'd been shooting the previous weekend. He seemed delighted to be in the countryside, negotiating with farmers and fishermen rather than Knightsbridge traffic.

The menu reflects the twin obsessions of David and Pascal. From a fish-heavy choice of starters (smoked salmon, lobster salad, roast sea trout) my south coast scallop beignets and crispy squid was fabulous – the scallops fat and mouth-filling with that quality of freshness that makes them slightly sweet, the tempura like a clothing of angel's breath.

Crispy squid was less exciting, but basked in a bed of shaved fennel, coriander and sweet chilli salad. Ravioli of goat's cheese with spinach and pine kernels arrived on melba toast, offering a welcome crunch against the delicate, melting pasta. A heritage-tomato sauce was finished with basil pesto and a kiss of balsamic.

When we reached the evening's specials, I expected to see evidence of cheffy rivalry between David and Pascal – a cook-off of fish against game. Instead, there was a harmonious intertwining of influence.

David the fish maestro offered 'roasted south-coast cod with Selsey lobster dumpling', but into this already-rich duo Pascal had introduced 'Brittany Paimpol coco bean truffle cassoulet' with sauce bisque. It was a crazily complex dish, with three major items wrestling for the upper hand, and a sauce derived from the pearly-white and creamy Breton 'demi-sec' beans which have a season of only seven weeks.

The lobster dumpling was pure luxury, the cod couldn't have been fresher, plumper, whiter, or more redolent of the bounding main, and the cassoulet somehow wasn't allowed to dominate.

Pascal the game specialist showed off with 'slow-roasted partridge and wood pigeon breast and confit leg'. That's right – one bird cooked inside the other, like the legendary medieval banquet dish that started by stuffing a wren into a sparrow and finished by shoving a swan, stuffed with 10 other birds, inside a great bustard.

The partridge inside the pigeon was heftily textured and very gamey indeed, the duet of birds amazingly unctuous and rich; not for faint hearts or small appetites. A caramelised onion compote was fine, and a cream ruby port salsify offered a startling combination of flavours, but by halfway through, I was aching for something green to offset the dark heaviness of it all.

Choosing a pudding (under duress, following such a blow-out) I went for a liquorice and lime parfait with poached spiced pineapple; it was brilliantly executed and unexpectedly (liquorice parfait!?) harmonious. And our maître d' Richard, the most charming and chatty greeter I've met in ages, bunged us a Tokay pudding wine gratis.

The Leconfield offers a cornucopia of English food, exceptionally well cooked and now given some sexy Breton touches. I just hope the rivalry between the chefs doesn't result in too richly bulked-out dishes (or, indeed, diners' waistbands).

Food ****
Ambience ***
Service ****

The Leconfield, New Street, Petworth, West Sussex (01798 345111). £130 for two with wine