"I am not an American, I am the American," Mark Twain is quoted as saying at the start and close of Mark Twain, Ken Burns' adoring documentary of the writer and satirist's life. Coming from anyone else, such a line would seem comically hyperbolic. More than any other writer, however, Twain has earned the right to make such a claim, and not just because Ernest Hemingway famously said that American literature began with Huckleberry Finn. A towering icon of Americana, Twain personified many of the contradictions that would come to define his country. A fearless friend of the downtrodden, as well as a shameless social climber who wasted his fortune trying to increase it, Twain is a natural subject for Burns, who has previously explored such unmistakably American subjects as baseball and jazz. Originally aired in two installments on PBS, Burns' three-and-a-half-hour Mark Twain finds one American institution paying homage to another, and the result, at least initially, is near-toxic levels of Americana. But the film grows richer and more ambiguous in its second half, as the trouble in Twain's life evolves into full-on tragedy and despair. Born Samuel Clemens, son of a Missouri slave-owner and failed businessman, Mark Twain derived his pseudonym from a nautical term signaling either the spot where dangerous water became safe or where safe water became dangerous. It proved to be one of the most memorable monikers in American literature, as well as a fitting metaphor for Twain's alternately blessed and cursed existence. As Twain grew up on the banks of the Mississippi, his psyche was formed as much by the harsh existence and colorful tales of the neighborhood slaves as by the childhood mischief that later inspired classic novels like Huckleberry Finn and Tom Sawyer. An ambitious young man with a wandering spirit, Twain traveled throughout his early life, working as a steamboat pilot, a failed prospector, and a typesetter. But as a writer, he made his mark, and for much of his adult life, he was among the best-paid and most popular authors in the country. He was also a desperately lonely man and a terrible businessman who endured horrific trialsmost notably, the early deaths of three of his four children, as well as his saintly wife. Like its subject, Mark Twain grows darker as it progresses, as Twain loses his faith and turns on a God who burdens him with hardship after hardship. Burns acknowledges Twain's depressive streak throughout, but the portrait that emerges here is unfailingly worshipful and sympathetic. Burns comes to praise Twain, not to bury him. Mark Twain elevates its subject, turning a figure too often depicted as an impish caricature into a brilliant, complex, and troubled man whose talent and humanity were all the more remarkable for having emerged from such deep reservoirs of grief.