The prehistory of psychedelia gets an interesting, if minor footnote with this documentary co-directed by Alex Gibney. In 1964, bestselling writer and novelist Ken Kesey became a counter-cultural legend for a chaotic road trip he took across the United States in a rickety school bus, taking with him a bunch of "Merry Pranksters". The journey was recorded in a book by Tom Wolfe, but Kesey also shot hours and hours of amateur cine film – forgotten for decades – which this documentary reconstructs and edits into shape. It's an intriguing window into a forgotten time, after beatniks yet before hippies: a rather innocent world, in fact. 
Peter Bradshaw
The Guardian