I watched the film, and there’s a brief shot where Lennon surreptitiously takes some small item out of his pocket, notices that the camera is on him and then puts it back in his pocket. Not sure what was going on there, but my hunch was some sort of drug use. There are definitely days in the documentary where Lennon seems strung out on something. Helluva musician, though.
I have a copy of The Beatles Anthology, and in it John Lennon recounts that late in the Sixties (maybe even early Seventies) he had a small bowl full of powdered hallucinogen near his front door. As he left or entered the house, he would wet his finger and dip it in the bowl, then lick it off.
I forget the time frame, but I think he did this constantly for a period of months. Eventually he said that he was walking around with the color completely washed out of his world, he was seeing everything in black and white.
Good gosh. I can understand someone catching a buzz, but someone has to be so afraid of reality that they would do that.
Of course, he was, at the same time, using every other drug under the sun.