Intense and swelling, "Bad" was often the centerpiece of U2's live sets throughout the Eighties. The lyrics – grim and desperate in the verses, triumphant in the chorus – were impressionistic enough for listeners to read any personal struggle into them. By 1987, however, Bono was introducing it as a song about addiction. "I wrote the words about a friend of mine; his name was Gareth Spaulding, and on his 21st birthday, he and his friends decided to give themselves a present of enough heroin into his veins to kill him," he told an audience in Sweden that year. And at a Chicago performance, he focused on the societal effects of the drug, introducing "Bad" as "a song about a drug called heroin that's tearing our city in two, that's tearing the heart out of the city of Dublin, tearing the heart out of the city of Chicago."