Trannack turned right and drove down onto the beach, 80heading towards an impressive mass of rock which marked the beginning of the causeway. ‘That’s Chapel Rock,’ he said, slipping effortlessly into the role of guide. ‘The pilgrims used to wait there for the tide to go out, but they pulled the chapel down during the Civil War.’

‘Which side were you on?’

‘The right one, of course,’ he replied, without missing a beat, then added: ‘We held out for the King as long as we could. The Prince of Wales stayed at the Mount on his way out of the country. There’s a little room off the south terrace where they hid him – you’ll see it later on, no doubt. Mind you, the current Lord’s ancestor was for Parliament, but we don’t hold a grudge down here.’

He smiled at her in the rear-view mirror, and Josephine remembered how welcome she had felt the last time she was in Cornwall, staying with Archie’s family. ‘Do you live on the island?’ she asked, already fascinated by its history.

‘Yes, in the village. My family’s been there since the seventeen hundreds, but that’s not unusual. Most of us go back a few generations, usually doing the jobs our fathers did. There’s not as many of us as there used to be, mind, and even fewer since the war, so you have to be able to turn your hand to most things now.’

The car took the causeway slowly, its tyres bumping over the cobbles as they left the mainland behind. On either side, flocks of oyster catchers searched for food along the shoreline, plunging their bills deeply into sand left bare by the fallen tide, and the smell of seaweed was rich and pungent. Up ahead, the path’s halfway point was marked by a square stone embedded with a cross, another reminder of the island’s holy origins; the image was already stark, silhouetted against 81an increasingly angry sky, but a carrion crow perched on the upright post gave the scene a still more ominous appearance. ‘Not exactly robins and festive cheer so far, is it?’ Marta whispered. ‘I hope they’ve lit the fires.’

Rachel Lancaster took a handkerchief from her bag to wipe some condensation from the window, and as the sleeve of her coat fell back, Josephine noticed a faint bruise on her arm. She would have thought nothing of it had it not been for the brusque exchange she had just witnessed, but now she wondered if the careful arranging of the scarf was down to something more disturbing than nerves. ‘Have you come far?’ she asked, conscious that the couple hadn’t spoken a word since getting into the car.

‘From London,’ Rachel said. ‘We live in Somers Town, near Gerald’s work, but we came down yesterday and broke the journey overnight. It’s our wedding anniversary today. This trip is Gerald’s present to me.’

‘You were married on Christmas Eve?’ Marta said. ‘That was brave, with so much to organise already at this time of year.’