The new HBO documentary "King in the Wilderness" chronicles the Rev. Martin Luther King Jr.'s final years, the most challenging time of his life. Striking images and footage plus interviews with friends reveal the man beyond the "I Have a Dream" speech. Allies say an equally meaningful speech was the one in which King made his feelings known against the Vietnam War - a courageous speech that earned him enemies. As the FBI sought to bring him down, King struggled against the rising anger of the Black Power movement and the "racial hypocrisy" that took root across the country. Ultimately, King sacrificed his life in his nonviolent fight. But lesser known are the mental and emotional tolls on him before his assassination in Memphis.