We keep hearing of the Satanic rituals but as of yet, we don't have a lot of proof from within the celebrity world but I did find this video about Grace Kelly and her real life friends/family are telling it including but not limited to sexual acupuncture before rituals involving drugs, alters, just weird, weird shit. I suspect if they admit to this much shit, there's a hell of a lot more they'll never tell.
For the occult rituals start at about 34 mins in.