Celebrity memoirs often focus on stereotypical subjects, like drug abuse and insecurity. How pedestrian! Thankfully Mackenzie Phillips, a former sitcom star and long-time drug addict, breaks boundaries in her new tome. And they're very unsettling.

Phillips, the daughter of The Mamas and the Papas singer John Phillips, confesses in her book, High on Arrival, that she and her father had a long-term, consensual incestuous relationship which began the night before her wedding. Um, ew!

My father was not a man with boundaries. He was full of love, and he was sick with drugs. I woke up that night from a blackout to find myself having sex with my own father.

Had this happened before? I didn't know. All I can say is it was the first time I was aware of it. For a moment I was in my body, in that horrible truth, and then I slid back into a blackout.

Later, John allegedly asked Mackenzie to run away with him. While we're all a bit revolted by this revelation, Mackenzie urges the public not to hate her father, who's now dead, and can't confirm nor deny the accusations.