The Deep End, 10 PM on FREE:

Filmed over the course of three years, this provocative four-part docuseries explores the world of one of today’s most controversial spiritual teachers and her dedicated group of followers.

Tonight’s premiere, “The Lost Toys,” introduces some of the main players in this world, where so many people are desperate to feel connected to something. Many of them gravitate toward this charismatic leader, who claims to be on a mission to end human suffering. The question, of course, is: at what cost?