In April 2011, Ai Weiwei, China's most famous living artist and most visible dissident, was arrested for "damaging state security" and detained for 81 days. During this time, he was held in a "humiliation unit" of a prison, then moved to a military facility where he was questioned daily about his activities and his intentions. In "Hanging Man," Barnaby Martin, an English friend of Ai Weiwei, offers a provocative and highly contextualized portrait of the artist — a dual portrait, in fact, of Ai Weiwei and of the Chinese Communist Party that has sparked his creativity.

Martin's commentaries on Ai Weiwei's artwork are enlightening. For Ai Weiwei, China is "the horn of plenty that has somehow gone wrong," and this theme is present in his early canvases, in the "ready-mades" crafted out of recycled materials, and in the large installations of the past 10 years. Martin explains how the form of art that Ai Weiwei produces challenges party-authorized art, a combination of Chinese folk art and social realism, which emphasizes that there is "only one permissible vision of reality." (The party's efforts to channel the artistic "vision" of its citizens has widespread parallels — in controlling the media and in censoring the Internet, for instance.) Strongly influenced by conceptual artists such as Andy Warhol and Jasper Johns, who re-envisioned the familiar by painting alternate versions of such icons as the American flag and Mao, Ai Weiwei has adopted an "alchemical method" where "nothing is sacred, everything can be transmuted into something else."

The best part of "Hanging Man" is the interview itself, and Ai Weiwei's account of his detention and interrogations is the most compelling piece of Martin's book. Ai Weiwei was not tortured; in fact, he was afforded rather delicate treatment. Nevertheless, he was handcuffed to a chair and subjected to round-the-clock surveillance first by policemen (later on, by soldiers) seated 2 feet away from him. Talking was forbidden. Ai Weiwei had no specific allegations leveled against him, no access to a lawyer, no assurance that he would ever be released. When the party interrogator accuses him of scamming the public and falsely defining himself as an artist, Ai Weiwei decides "to explain, to make them understand about art," and so begins an odd tutorial: The passion with which he defends artistic freedom impresses his questioners. Ai Weiwei also finds a means of communicating with his guards, who are embittered by the captivity of their jobs and empathize with him.

Martin offers much historical context. "Hanging Man" will help the newcomer to Chinese history appreciate the power of the Chinese state and the official apparatus it has brought to bear against dissidents. Martin's clear and expressive prose gives his reader much reason to value Ai Weiwei's creative brilliance and his bravery. If Martin goes off the rails at times — do we really need a few pages on the Beijing smog or a vignette of a Mexican admirer? — his report on the tension between artistic vision and authoritarian hegemony is nothing short of excellent.

Tom Zelman teaches English at the College of St. Scholastica in Duluth.