Archibald and Juliana Carriscant and their son Salvador… Commodore George Dewey and the battle of Manila Bay… The capture of Emilio Aguinaldo… Six hundred million dollars of American taxpayers' money spent on a forgotten and bloody colonial adventure half a world away… What did all this have to do with me? I wondered how it could possibly explain my journey to Lisbon with a man who claimed to be my father in search of a woman whose face I knew from a torn-out page in a 1927 pictorial magazine.

We had a rare and gratifyingly tranquil voyage on the SS Herzog. The Atlantic swell remained glassy and docile as we cruised eastwards through mild hazy sunshine, the fraying rope of smoke from our two tall stacks trailing persistently behind us as if reluctant to be dispersed on the gentle oceanic breezes.

During our ten-day journey Carriscant was as good as his word – he told me everything, and answered every interrogation I put to him without demur however embarrassing my enquiry or however damaging it might prove to the portrayal of his character and motives. As you will see, his candour was impressive. I kept copious notes of everything he told me and wherever possible attempted to catch him out or corroborate details. In the relaying of his story I have allowed myself some of the licence of a writer of fiction, have embellished it with information I obtained later and with facts gleaned from my own researches. But in the end this is Salvador Carriscant's story and I have had to trust the teller, as we all must in these circumstances, but what follows is, I believe, as close to the truth as anyone could come.

According to his best recollection, on the day of the first killing, Dr Salvador Carriscant – the most celebrated surgeon in the Philippines – suffering from a mild headache, left his house and decided as was his occasional habit to walk to work. Nobody of any importance or self-regard, with even the slightest modicum of selfesteem, walked in Manila in those days but Dr Carriscant relished the short stroll from his fine house on Calle de la Victoria to the San Jeronimo hospital, not only for the pleasant sensation of libertarian fellow feeling it provoked in him but also because the interlude allowed him to calm down, to forget the irritations and frustrations of his home life, and clear his mind for the exhilarating but complicated business of the day's work waiting for him in the surgical wards.

The San Jeronimo hospital in Manila was a comparatively recent building, having been completed in 1878 and renovated again nearly twenty years later when the electric light was installed. It was to some extent modelled, so Carriscant had been informed by an elderly member of the hospital's board of governors, on the Palazzo Salimberri in Sienna and certainly the streetfront facade bore some resemblance to a crude quattrocento building, made of well-cut adobe brick, with a simple hipped roof of terracotta tiles, much overgrown with ferns, moss and other greenery. There was a very high arched gateway with heavy wooden doors and a row of small square windows set in the walls above, bestowing a solid and uncompromising character, as if the place might have to be defended in times of insurrection or be called on to do duty as a prison. Inside, however, was a wide paved courtyard with arched cloisters on three sides and set behind that was a mature walled garden and arboretum crisscrossed by gravelled paths. Various consulting rooms for physicians, administrative offices and the dispensary led off the cloistered arcades, but the operating theatres, and there were two of them, were contained in two stubby projecting wings, east and west, on either side of the garden, almost as if they had been added as an afterthought. Dr Carriscant's theatre was in the east wing. The medical director of the San Jeronimo hospital, Dr Isidro Cruz, practised his art in the western projection.

The design of the San Jeronimo was simple and, as long as numbers of patients did not grow too rapidly, as they did when the cholera and smallpox epidemics erupted, was quite effective. Patients first visited the physicians on the ground floor who then, where necessary, referred them to the surgeons. Post-operative care took place in the wards that occupied the floor above. The one disadvantage of the place was that there were no laboratories or dissecting rooms and that the morgue was a little on the small side. Consequently any anatomical or experimental work had to be carried out at the San Lazaro hospital or in private premises. The reputation of the San Jeronimo had been high, almost from its inception, owing to the celebrated dexterity of Dr Cruz (who on one day in 1882 had performed over three dozen amputations) but it had been augmented in recent years as a result of Salvador Carriscant's return from Scotland in 1897 and his introduction of Listerism and the latest surgical methods and the remarkable success rate these innovations had produced. The hospital board had increased his basic salary four times and had awarded him the honorific title of surgeon-in-chief, a move that Dr Cruz had vehemently and publicly protested and which had set the seal on and, as it were, formalised the doctors' personal animosity to each other. In public the two men maintained an air of courteous but professional reserve, but everyone knew that Dr Cruz detested Dr Carriscant and everything he stood for medically. The feelings were reciprocal: to Cruz Carriscant was an obsessed faddist and heedless experimenter; to Carriscant Cruz was an antediluvian sawbones cum sinister circus performer, and so on.

Dr Salvador Carriscant passed through the wide arched gateway, acknowledging the respectful salute of the porter on duty. His headache was easing, he was happy to note, and he was looking forward to the first operation of the day, the extirpation of a large tumour from an adolescent boy's tongue. He was planning to make a new form of incision, one that would allow him to sew up the wound rather than sear it as was normal, in a way that should allow the lad to speak, after a fashion, once he had healed. Such extirpations were Dr Cruz's stock in trade, it took him a matter of seconds he boasted, like lancing a boil, but Manila was full of mumbling semi-mutes with needlessly stumpy tongues as a consequence of Cruz's heavy-handed speediness. If that day's operation proved a success it would further undermine Cruz's unwarranted eminence: the medical director of the San Jeronimo hospital would have even less work to do.

Carriscant crossed the courtyard towards his consulting rooms, noting that the waiting room was already full and there were half a dozen people sitting on a wooden form outside. He glanced over at Cruz's equivalent suite of rooms and saw that the main door was closed and the shutters unopened. Cruz's patients had declined steadily in the years since Carriscant had arrived and now it was either ignorance or agonised desperation that led anyone to demand a consultation with the old surgeon. He was a dying breed, was Cruz, Carriscant reflected, a historical curiosity, an emblem of the bad old days of the profession, but he was good with the knife, Carriscant had to admit, and his eye was impeccably sure. He was fast, Cruz – damned fast. The war had seen a surge in demand for his expertise, he had carried out hundreds of amputations, but since it had ended, business had slackened again and now the old man spent much of his time on his large ranch at Flores and in his personal laboratories which he had had constructed there and where he kept his hand in by operating on monkeys and dogs. Carriscant never forgot the first and almost the last operation he had performed with Cruz. Cruz had watched him washing his hands prior to entering the theatre. 'You prefer to wash your hands before the operation I see, Carriscant,' Cruz had commented acidly. 'I prefer to wash mine afterwards.' On his rounds of the wards too his brutal frankness was legendary: 'That's one of the worst cancers I've seen,' he would tell some suffering soul cowering in his bed. Or, 'The leg will have to go, off at the hip too, let's not take any chances.' Or, 'Conditions such as yours, my dear fellow, are inevitably fatal. I doubt you'll be seeing the outside of this hospital again.'