Plainly, Freedom Dreams: The Black Radical (published in 2002) tells the story of "Black, nationalist, communist, feminist and liberalist movements" throughout history. Kelley pays particular attention to the leaders of these movements and uses their works, as well as examples from his life, to illustrate his thesis.
In that sense, the book is about history. However, it's also a memoir. For example, in one of the book's stories called “When History Sleeps”, Kelley tells the story of his mother and her so-called "third eye" as it relates to politics. His mother was a smart woman and helped to inform his worldview and his thinking process' for much of his life, which is reflected in this book.
When discussing black movements, Kelley draws from the works of famous black thinkers like Martin Luther King Jr., D.E.B Du Bois, and Marcus Garvey to make the point that throughout black people's history, Black people consistently strived to be free. This shown, he argues, through their "exodus" and "redemptive" movements. This remained true in nationalist, communist, feminist, and liberalist movements throughout history.
At the end of the day, Kelley comes to a solution for some of the world's problems: if capitalism is obliterated, then the scourge of racism will go away with it. Kelley argues that capitalism creates evil and things life socialism are more fair, equitable, and accepting. To that end, Kelley argues that every capitalist country ought to be radically changed.