Short answers, pulled from the story.
Paul McCartney held a blank piece of white paper with a circle drawn on it and proposed the project during the summer of 1967. The idea originated from Ken Kesey's cross-country bus tour aboard Furthur with the Merry Pranksters.
Shooting took place between September 11 and the 25th of September 1967 across the decommissioned airfield in Kent. Ten hours of footage were captured over two weeks before editors trimmed the final cut down to fifty-two minutes.
Four magicians appear at random moments to cause strange things to happen to the passengers while three are played by the Beatles themselves. Mal Evans takes the fifth role alongside Ringo Starr who sits in the front seat of the colorful bus.
BBC1 broadcast the film in black and white on Boxing Day the 26th of December 1967 despite it being a color production. George Martin later stated that showing the color film in black and white made it look awful and was a disaster.
Only about 200,000 color television receivers existed in the UK when BBC2 re-aired the program on the 5th of January 1968. Networks in the United States declined to show the film following the unfavorable reviews.