On film, as on stage, Janis Joplin is like a child in complete isolation: holding dialogues with herself that never end, moving gently over her own pain like someone trying to compose an instant autobiography. It's a tribute to the makers of this documentary that you do come out feeling that there will never be anyone else like her. The film contains no mention of her death, only the merest suggestion in a wistful tracking shot around her empty car, but from the amount of energy that we see released it doesn't seem surprising. Her own words, plus a montage of early pictures, go quite a way towards explaining how the quiet suburban kid from Port Arthur who was never asked to the High School prom could have developed into one of the greatest American rock singers. Alk and Findlay simply allow the story to be told in its own terms, especially by the performances: all of the good ones are here, from the legendary Monterey 'Ball and Chain' to 'Try'.