The prince of darkness returns

    Few things in art are as sexy as the rediscovery of an old master. It’s like finding an envelope crammed with ancient stock certificates down the back of grandad’s settee. It doesn’t happen often, of course, but it does happen. Vermeer was entirely unknown for three centuries before his rediscovery in the 1860s. More recently, and more astonishing still, Caravaggio was a name and not much else until a brilliant Italian art historian, Roberto Longhi, unleashed his output on the world in 1952.

    The freshest example of the mouthwatering turn-up can be dated firmly to 1972, when a show opened in Paris devoted to a previously invisible 17th-century French master called Georges de la Tour. A couple of determined scholars working in his territory had known of his existence, but not many others. The few, precious examples of his output gathered in Paris in 1972 revealed a style that was utterly tangible yet thoroughly mysterious. La Tour painted night scenes as nobody had painted them before. A flickering candle. An illuminated face. Something going on in the dark, but what? Obviously, he was a distant follower of Caravaggio, but his colours were weirder, his moods more tender, his vision stranger.

    Since that pioneering rediscovery, a modest array of facts has been appended to the mysterious name. Georges de la Tour was born in 1593 in the small medieval town of Vic-sur-Seille, Lorraine, but in 1620 he moved to the aptly named Lunéville – Moontown – where he spent the rest of his life, painting in isolation, until his death in 1652. Nobody is certain where he encountered Caravaggio. There were no Caravaggios in Lunéville, or anywhere nearby. Most probably, the lessons were learnt at second or even third hand from Caravaggio’s Dutch followers. But the lack of contact with the artistic mainstream is precisely what made la Tour what he was. Isolated in Lunéville, fiddling away gloomily on his own, he developed a thoroughly idiosyncratic and unmistakable style. Once you’ve tasted la Tour, you always recognise the flavour.

    His known output is tiny: about 40 pictures. So every la Tour exhibition is an event, and I set off for rural Warwickshire, where one has miraculously popped up at the pretty Robert Adam mansion of Compton Verney, twitching with excitement. And found a minuscule show. Just five paintings, one of which is assigned here to la Tour’s son, two of which have been the subject of constant speculation since they were discovered, and two more of which are probably by him, but not yet certainly.

    The Queen has lent a small three-quarter-length of St Jerome reading. Remarkably, it entered the Royal Collection as early as 1660, bought by Charles II, and therefore offers exceptionally rare proof of a British monarch exhibiting perspicacity and good taste. Most Jeromes in art are frail and saintly greyheads in their eighties, but this one is in his mid-sixties or so, balding, red-nosed and the possessor of a grumpy human presence worthy of a shortsighted bookkeeper checking accounts. Making saints feel human was standard baroque practice – one of Caravaggio’s best lessons.

    Where this painting is unmistakably la Tourish is in its lighting and its colour scheme. Jerome is always identified by the red cardinal’s cassock he wears, but never before has his costume glowed as fiercely, as if illuminated from the inside like a chinese lantern. The candlelight penetrates the letter he’s reading, too, and gives it a red glow. It’s an intense nocturnal moment, not just a description of an elusive set of light conditions but an evocation of a strangely fraught nocturnal mood.

    A couple of the rooms have only one painting in them. One ambitious room has the other three. So the display will certainly disappoint more visitors than it excites. But the virtue of a show as small as this is that it forces you to examine every picture extra-carefully. St Sebastian Tended by Irene is almost all nuances. Painted in the early 1630s, it shows – or implies – a rather sexy St Sebastian half-naked in the dark, leaning back on a pillow while the young widow Irene, his illuminated nurse, pulls a large arrow out of his leg. Most St Sebastians in art bristle like porcupines with Roman arrows. By reducing the number to one, la Tour focuses the drama on a single moment of pain. And setting the action in the dark adds mystery and, dare I say, romance to these secretive goings-on.

    Am I merely the possessor of a dirty modern mind, or is there something deliberately phallic about the upright arrow, and something naughtily poised about the proximity of the widow Irene’s mouth? Her tenderness is indisputable, but isn’t there also a hint, a whisper, of fellatio? That’s what you get with night scenes. That’s what you get with la Tour. Some of the action takes place in the picture, but most of it happens in your imagination.

    The St Sebastian has come here from the Kimbell Art Museum, in Texas, and the way the picture glows, like a mahogany table that has fallen into the hands of an overenthusiastic french-polisher, is typical of American tastes in restoration. Television cupboards in American hotels have the same deep, artificial shine. For what it’s worth, I recognise here the clear influence of Rubens in his Caravaggesque phase, as exemplified by that dramatic Samson and Delilah in the National Gallery.

    Obscure though he became, la Tour was obviously a much-admired painter in his time, to judge by the large number of copies and reworkings of his pictures that have survived. Interestingly, his son, Etienne, who was undoubtedly responsible for many of the copies, is being recognised as worthwhile in his own right, broadcasting his father’s methods and amplifying them. This show proposes that a charming image of the obscure St Alexis, who lived and died under a staircase, and whose body is shown here being discovered by a servant with a torch, is by Etienne.

    To my shame, until I read the catalogue, I had that painting down as the only definite la Tour here. What threw me was the woodenness of some of the faces in the other pictures, the uncertainty of the flickering light effects, the awkward poses. St Alexis’s painter seemed more secure in his anatomy and his physics. But it’s true: those are the perfections you find in a follower, not in an originator.

    Because the la Tour show is so small, Compton Verney has paired it with a display of contemporary art devoted to The Shadow. It’s an obvious theme, but an entertaining one. Fiona Tan gives us Downside Up, a tricky video in which some scuttling figures and their shadows swap places as they hurry across the screen. And I admired Mona Hatoum’s simple but effective installation, Misbah, named, I presume, after the Scottish teenager Misbah Rana, who ran away to Pakistan to be with her father. A vaguely Islamic prayer lantern of the kind you might find in a mosque throws fleeting shadows on the walls as it revolves in a dark room. The shadows never settle, but they seem to show the agitated outline of an advancing squad of gun-toting soldiers. Thus, religion and violence take to the shadows and embrace: how well we know this subject.