Chapter One The Blackett Strait, Western Solomon Islands, approximately 2.30 a.m., 2 August 1943 The japanese destroyer came out of the night at forty knots like a huge shark snarling across the lagoon. It struck the small American craft and cut it in half before disappearing into the blackness. Part of the fragile plywood and mahogany vessel sank almost at once, with two of the thirteen-man crew already dead. Sprays of gasoline were flung across the surface of the water, burning intermittently.    The young lieutenant in command of the craft had been at the wheel when the ramming had occurred.

Fearing that the flames spreading across the water might reach the chewed-up remnants of the vessel and destroy them, he ordered the survivors over the side. In seconds, the crushing wake of the already invisible destroyer had extinguished the blaze. The eleven survivors, two of them badly hurt, hauled themselves back on board.    They remained huddled on the fractured, water-slopped deck until daybreak. As the sun edged over the horizon, the two ensigns and eight enlisted men looked to the lieutenant for instructions.    ''What do you want to do if the Japs come out?'' he asked. ''Fight or surrender?''    The remaining half of the plywood coffin began to settle in the water, almost obscuring the inscription on its splinter shield: PT-109. Chapter Two ''The problem is,'' said Sister Brigid, loudly enough for Sister Conchita to hear above the noise of the crowd, ''when does an inconvenience transcend into sacrilege?''    Sister Conchita smiled sweetly and resisted the temptation to batter the elderly Irish nun about the head and shoulders with one of the carvings for sale on the table by the door leading to the refectory.

On display were ebony walking sticks inlaid with mother of pearl, patterned pandanus baskets, vicious-looking stone war clubs and the engraved prows of several miniature war canoes, known as toto iso. Sister Jean Francoise should have been in charge of the stall, but Conchita could see the French nun through the open window, her habit hitched above her scrawny ankles, paddling contentedly in one of the rock pools on the white-sand beach, ignoring the visitors eddying around her. That left only Sister Johanna, and she almost certainly would be engrossed in dismantling and reassembling a piece of domestic machinery somewhere in the building.    In the reception room of the old stone building, the visitors to the mission''s first ever open day surged through the doors and out into the gardens leading down to the reef and the open blue sea beyond. Behind the house, wooded foothills swelled in green profusion until they merged into the extinct volcanic mountain in the centre of the small island. Marakosi was a beautiful enough mission station; it was a pity about the three elderly rapscallions who had made up its religious complement for so many decades and who were slowly driving Sister Conchita mad.    ''It''s all very modern,'' said Sister Brigid in a tone that emphasized that the word was not meant as a compliment.    ''Please keep circulating,'' Sister Conchita exhorted the visitors, continuing to ignore the older nun.

There was hardly room to move inside the house. ''The whole mission and its grounds are open to you today.''    ''And don''t we know it,'' said Sister Brigid loudly, to no one in particular. ''There''s not room left to swing a cat.''    There was no doubt about it, thought Sister Conchita, smiling until her face hurt, she would have to fetch Sister Jean Francoise back inside. The elderly French sister might be as crazy as a coot, but at least she seemed to have some influence on Sister Brigid. Perhaps she could keep the acerbic Irish nun quiet until the guests had left. It definitely was time to clutch at straws.

Brigid was a sour, withdrawn woman who spent most of her time as far as Conchita could make out standing on the reef staring out at the lagoon. Officially she was in charge of housekeeping at the mission, but the layers of dust everywhere and the dreadful food they had been eating for the last month bore witness to her lack of commitment in these areas.    ''Excuse me,'' said Sister Conchita brightly, pushing through the throng like a very small but extremely determined running back. There were at least sixty visitors in the room and another two or three hundred scattered about the mission building and grounds. They were mostly Solomon Islanders, bolstered by a few expatriates from the nearby tiny district centre of Gizo, all attracted by the prospect of seeing what the notorious Marakosi Mission was really like. Leavening the attendance was a group of bewildered-looking American tourists who were staying at the government rest-house over at Munda, a nearby island. The Solomons consisted of a string of hundreds of beautiful and remote tropical islands, five hundred miles east of Papua New Guinea and a thousand miles north-east of Australia. The islands were difficult to reach, and the tourist trade was in its infancy.

   There was a human logjam at the door leading to the small in-house chapel used by the sisters for their private devotions. A bulky female American tourist in shorts stretched dangerously across her thighs had stopped in the open doorway and was brandishing a carved model of a turtle above her head.    ''Where do I pay for this?'' she demanded.    ''We must all pay for our transgressions eventually,'' said Sister Brigid coldly before Sister Conchita could reply, her voice rising and falling like a dagger plunging with deadly accuracy into a body. ''How and when lies in the hands of the Almighty.''    Not if I get to you first, Sister Conchita promised herself vengefully, squeezing past and emerging from the front door of the two-storey mission house on to the stone terrace leading to the beach and the calm lagoon beyond. Blocks of coral jutting out into the sea broke the force of the waves thundering against them in the distance beyond the reef and provided a safe anchorage for smaller vessels. She stopped outside, luxuriating in the sudden peace, although even here her mind was registering automatically the improvements needed.

The ancient and cracked mission bell used to regulate the nuns'' day with its strident summonses to matins, lauds, vespers and compline was suspended from a crossbar between two wooden posts that needed strengthening. It was tolled from the first sunrise Mass, and then regularly through the day to summon the nuns to meals and work sessions, ending with evening prayers.    Those visitors who had escaped from the heat of the house were scattered across the sand. The flower beds around the mission were overgrown and unkempt. A vegetable patch had surrendered almost completely to rough grass. Chickens and pigs wandered unchecked around the fringes of the crowd. A few dispirited yams struggled through the baked earth. It would not have been difficult to rotate the crops, with sweet potatoes following cabbage, but no one had made any effort to do so.

   Conchita could not imagine why so many visitors had turned up. It might not be much, she thought, but the open day was probably the most interesting thing that had happened at the mission for generations.    There was so much to do, and it looked as if she was going to have to do most of it herself during her stay, she agonized, heading for Sister Jean Francoise, who was still paddling happily, oblivious to the strangers all around her. Like the other two nuns on the station, she would be well into her seventies now, small and bird-like in her movements, her face lined and weathered brown by the sun, but still possessing traces of the pretty and vivacious country girl she must once have been before she came to the Solomons.    ''Sister Jean Francoise,'' coaxed Conchita. ''We really do need your help in the mission. Do you think you could possibly spare us an hour or so?''    The French nun looked up from contemplating the smooth surface of the rock pool. She smiled beatifically, radiating an all-pervading charm.

   ''In the mission?'' she asked with only a faint trace of an accent. ''But I am the laundry and garden sister. I seldom enter the mission except to eat, pray and sleep.'' She paused, and then giggled. ''Almost literally I have been put out to pasture.''    ''Even so, it is our first open day. There are so many people here. We could do with your help.

''    ''Open day?'' Sister Jean Francoise looked about her vaguely, as if seeing the visitors for the first time. ''Oh yes, I remember something about that. An effort to modernize us, I believe. Throwing the mission open to the public. I don''t understand. It is most unlike Father Karl to approve of such a thing. He is a very private man.''    ''I''m afraid that Father Karl is dead,'' said Sister Conchita.

   An expression of sadness passed over the elderly nun''s face. ''Oh yes.'' She nodded. ''Now I remember. The poor man was ill for so long. You know, he got quite senile towards the end. It must be very sad, when your mind goes.'' She started hopping around the pool again, sending up tiny splashes of water.

''I believe they''re sending a sister from Honiara to run the mission until a new priest is appointed, some American girl with a strange name. I wonder when she will arrive.''    ''I''m the new sister in charge,'' said Conchita. ''I''m Sister Conchita. I''ve been here a few weeks now.