It’s full of prisoners, addicts, and other problems that society would prefer to sweep under the carpet. Hei Ling Chau is a small island close to Lantau, just to the east of Mui Wo: It’s the island on the left as you get the ferry to Silvermine Bay. On the southern side of the island is a typhoon shelter. But the island itself has a most curious history. Originally called Nai Gu Chau (“Nun’s island”), it was first settled in the 1890s by the Lam, Tsang and Ng clans, hitting a population of about 100 people by 1950. But after World War II and mass immigration following the Chinese Civil War, poor hygiene and rampant poverty led to widespread leprosy in Hong Kong. Back then leprosy was a feared and incurable disease, and sufferers were forcibly removed from their families to prevent further infection. In 1950, the government set up a leper colony—or “leprosarium”—to provide care and treatment. They chose Nai Gu Chau, paying the residents to move away and renaming it Hei Ling Chau—”Island of Happy Healing,” or “Island of the Joyful Soul.” At its height in the 60s, Hei Ling Chau was home to 540 lepers, an isolated island in the middle of an exploding city. Leprosy cases began to tail off in the 70s and the colony was finally closed in 1974, with the remaining 50 cases decamped to Lai Chi Kok Hospital. The Correctional Services Department took over and the island was used to detain Vietnamese refugees in the 1980s. Even to this day, Hei Ling Chau houses those who are there against their will: It possesses a medium-security prison and three government-run drug rehab centers, the largest of which is the Hei Ling Chau Addiction Treatment Centre. After all, if you’re going to rehab, it’s probably a good idea to put you in a location where your nearest score would involve a swim. A 2004 plan to build a super jail on the island was shelved thanks to public outcry, but Hei Ling Chau nonetheless remains an island of the incarcerated and the addicted. At latest count it held 870 souls in all. 870 people on the Island of Happy Healing, hoping for just that.