What do an heiress, an actress and the Dalai Lama have in common? A charismatic, but problematic, self-proclaimed self-help guru named Keith Raniere. As the founder of NXIVM, a marketing organization focused chiefly on self-help seminars, he was arrested for sexual abuse, and his organization was designated a cult. A new HBO docuseries, “The Vow,” examines the rise and fall of NXIVM. Directors Jehane Noujaim and Karim Amer join us to discuss.