Given the Hollywood movie as well as Tim Pat Coogan's respected biography, it would seem that readers would not need another bio of Michael Collins much less a 500-page one. But Peter Hart's "Mick: The Real Michael Collins" claims to offer a new perspective on the life of the Irish rebel leader. Hart is the Canada Research Chair of Irish Studies at Memorial University of Newfoundland as well as the author of The I.R.A. and Its Enemies. Hart offers insight into previously unknown sources, and is the first author to take a close look at Collins' life before he became a famous revolutionary. By the time he was assassinated at the age of 31, Collins had participated in the Easter Rising of 1916, formed the Irish Republican Army, outwitted British spies, pioneered guerilla warfare, negotiated with the British, and paid the price with his life. Some readers may be turned off by Hart's revisionist take on Collins. He argues that Collins was more of a politician than a soldier, whose legacy as an Irish liberator is far from clear. This may anger fans of what Hart sees as a kind of Collins mythology, but Hart makes a game argument, even if it is not one that certain readers will choose to buy. ($27.95 / 480 pages / Viking)