WITH ALL THE CHATTER across the late-night talk landscape, a certain sentiment keeps rearing its ugly head: When Conan O'Brien took over at 11:35 pm, his comedy suffered. For a wider audience, it had to be diluted, but in Conan's case it got neutered. For Craig Ferguson the same forces are at play. Even after midnight, the soapbox of a major network is constricting for a man of Ferguson's charming derangement. Although there are hints of his sordid past and twisted ideas on his Late Late Show, Ferguson airs out the stunning depravity of his alcohol-soaked life in American on Purpose, his recently released autobiography.

At 13, the young Scot visited New York. His cousins took him to Blue Öyster Cult and for the first time, Ferguson smoked pot. "From this moment on," he writes, "I would dedicate my life to rock and roll and take as many drugs as possible."

At 16 he dropped out of high school and fell in love with British punk. It was a golden age, the mythical summer of 1977, and Ferguson dug them all: the Sex Pistols, the Clash, the Rezillos, the Damned, and more. He pounded the drums in shitty bands, shared scorched flats, and woke up on floors. There was hash, heroin, acid, coke, and sulph ("poor man's coke"), but drinking became the prime evil. There were fights, wives, and women. Living in the East Village in his 20s, Ferguson picked a fight with a pimp, who pistol-whipped him and aimed. "This is it," he figured. But his drinking buddies, who Ferguson suspected were IRA members, shouted the pimp down.

The story of the tortured comedian is not uncommon (Richard Pryor immediately comes to mind). For whatever reason, certain comedians become empowered, twisting their darkness into laughs. American on Purpose, written lightly and sharply by Ferguson, is more than a dismal retracing—it's a story of redemption (getting sober) and an immigrant's actualization of the American dream (becoming a US citizen). Of course, there's also stand-up comedy, and Ferguson's discovery of the peace and success within.

On TV, Ferguson's style is already anarchic, and his ability to riff is unmatched. To see him free of the shackles set by Standards and Practices makes this writer salivate. Because if American on Purpose is any indicator, Ferguson's standup will be a welcome surprise.