I remember when I heard about the Dolphinarium bomb, as I turned on my computer in my office in the grimy heart of London's West End, the day after it happened.

News stories of innocent Israeli civilians killed by bombs were as familiar in 2001, as tales of the slaughters in Iraqi market places today, but for me the Dolphinarium attack, a night club in Tel Aviv in which 23 young people were killed and hundreds injured, was different. For once this modern tragedy touched me as it should — rather than the depersonalised shrug, or perhaps a brief frown, with which I heard other such terrible news. 

I did not at the time have any particular connection or even sympathy with the state of Israel. The Jewish people I knew, my neighbours, friends, and colleagues, I did not associate with Israel. They were no less "London" than me, and those with two English parents were more so. But I could not stop obsessing about  those young people waiting outside the night club on that Friday night, a child called Sasha who lost both his sisters, a fifteen-year-old girl celebrating the end of her exams, a social worker (the oldest of the dead) walking past at random. Haunting me most was Sheva-Moffat, the high school in a Tel Aviv suburb where there would be six gaps at assembly when school resumed.

And the bomber — what about him? He was described in the press I read, as a textbook crazed zealot. Was he a hardened paramilitary, a psychopath? How else could someone release a bomb packed with screws and ball bearings in a crowd of predominantly teenage girls? Looking at his photograph he looked more like a fearful schoolboy, ill-advisedly trying to grow a moustache.

Of course, I was affected by the age of the victims, but there was also the banal coincidence that I had once been a DJ of sorts. I'd play records at parties, weddings and sometimes clubs where I was hired for the slightly rare music I owned rather than my appalling mixing. For a certain period of my life enticing people to dance was the single most important activity in my little life. Doubtless this was at least part of the source of my empathy for those young people outside the Dolphinarium. Whatever it was, I identified with them, I could feel their yearning, their excitement, as they waited outside a nightclub on a Friday night. And that identification started a quest for information that lasted a decade.

The day after the blast, a Palestinian called Mazan Joulani was shot though the neck in Jerusalem. He was a pharmacist, not politically active, a family man with three young children trying to lead an ordinary life. Like the young people outside the nightclub, he was completely innocent. His family's response to their tragedy was to offer his heart for transplant and a few hours later Dr Yakov Lavie, a cardiac surgeon in the Tel HaShomer medical  centre — where many of the young people injured in the blast were  being treated — received a phone call from the Israeli transplant coordinator explaining they had a heart for one of his patients. That patient was Yighal Cohen, an Israeli father-of-two who had trained as a technician but was working as a salesman for L’Oreal.

So, a human heart was transplanted between a Palestinian Muslim and an Israeli Jew.  And perhaps this is why the story hit me at a deeper level, going back to my childhood, to the place all our stories begin. My father was, and my mother is, a pioneering cardiologist, I grew up amidst hearts — they were the defining phenomena of my childhood both in symbol and actual form. Occasionally they even appeared in the family fridge. When my mother lost a patient and did not understand why, she would keep the organ and examine it until its dysfunction was revealed.

Yakov Lavie performed the operation a few hours after the heart became available. As he  left the operating theatre, he said: "I was just holding the heart of an Arab Moslem in one hand and an Israeli Jew in the other and do you know what ? There's no difference"

Within a week Cohen was out of bed and taking his first steps. Meanwhile the story of the transplant had become a global sensation. Dr Lavie, a heart in each hand, experienced something like a secular epiphany; identity, and religion had in that visceral moment lost so much substance. As for nationality -it was for this these children were killed outside the Dolphinarium on June the 1st ,2001.  Not for being Jewish, but for being Israeli -and for nearly all these young people, being Israeli was a new identity, a new nationality - all but one were recent emigrants from the former Soviet states - their parents pulled by what lures most immigrants - the possibility of a better life. Many had grown up not knowing they were Jewish -or could be classed as such  , some were not Jewish at all -certainly halachially -but this did not worry the strategists behind this brutal bomb, they were Jewish enough to become Israeli and that was enough.

For me, this tragedy and the transplant after became the defining work of the next seven years of my life; travelling to Israel and the West Bank, finding those who had been there on the fateful night, speaking with their friends and families, interviewing Dr Lavie the surgeon, tracking down the suicide bomber's family and contacts; speaking to activists, extremists, peaceniks and terrorists and, of course, immersing myself  in every detail of heart transplants. 

I've asked myself what it was that moved me and continues to move me about the transplant  and it is many things, but one of them is the simple word, grace. It is a word rooted in the Roman Catholicism of my childhood, however its force moves beyond any religion, it does not even require an omnipotent God or a god at all, it  is something that (as Philip Larkin wrote)...falls as they say love should/
like an enormous  'yes'.  

Beat —The True Story of a Suicide Bomb and A Heart by Rowan Somerville, is published  by Lilliput Press