In the early hours of the morning of 1st July 1937, Gerald Edward Mary O’Brien was detained by police officers on the ferry returning from Dieppe. He had crossed the channel with six grammes of high-quality heroin concealed about his person. It was the last of what had been a regular series of trips to Paris from his home in London, and he had sourced the heroin from two young Americans living in a hotel in the Pigalle, which was the entertainment and ‘vice’ district of the French capital. The transaction was a small part of a broader global network overseen by Corsican and Sicilian organised crime groups; the poppies were grown on the Anatolian plains of Turkey, the opium shipped to Marseilles and converted to heroin in illicit French laboratories before arriving in Paris and being taken on to North America and around the world – the early, rudimentary beginnings of the famous ‘French connection’ that would take heroin to the mean streets of North America in the postwar years. The Paris route to London was a minor facet of an increasingly global trade.