Photo: Lionsgate/Everett Collection Early in American Psycho , Mary Harron ’s blisteringly good adaptation of Bret Easton Ellis ’s 1991 novel, Patrick Bateman walks us through a typical morning. The 27-year-old investment banker and possible serial killer strolls around his Upper West Side condo in a pair of white cotton briefs that match the place’s stark décor, his exposed musculature as sleek and defined as an action figure. “I believe in taking care of myself, in a balanced diet, in a