I know what you are talking about that chopping head part. I even knew that from childhood. This guy wanted to be saved or something and a guru had told him that in order to save ur self or something, you must keep repeating the name "ram" over and over. ANd while he kept saying ram ram ram, he was indulged by evil or something so he started saying "ra" "ra" "ra"which actually in sanskrit is a root for rakesh. So then the guy kept meditating on ra ra ra and became evil or something. So he was eventually killed like good over evil. SOmething like that.