Writer-director Paul Thomas Anderson follows There Will Be Blood with The Master, another story about a monomaniacal sociopath who ruins the lives of virtually everyone he meets — even those whose lives were in ruins to begin with. Philip Seymour Hoffman was nominated for a Best Supporting Actor Oscar for his portrayal of the titular Master, Lancaster Dodd, who (modestly) describes himself as "a writer, a doctor, a nuclear physicist, and a theoretical philosopher." To the viewer, however, he mostly seems like a cult leader and a con artist, peddling nonsense to weak-minded acolytes — none weaker or more vulnerable than maladjusted WWII veteran Freddie Quell (Joaquin Phoenix, who was nominated for a Best Actor Oscar).
Anderson has been coy in interviews about whether The Master is a fictionalized biopic of L. Ron Hubbard, the founder of Scientology.
Apropos of nothing, have you read Lawrence Wright's Going Clear? Both it and The Master are interesting works of very different stripes, and are both worth checking out.