Finn Wittrock has one of those faces. Chiseled and handsome. He looks sweet and approachable if that’s what the role calls for. He can also look disturbed or cruel or manic or plaintive. He has that rare talent of manipulating the tiny muscles in his face, infinitesimally tweaking his facial architecture to suit the characters he plays. This has come in handy in his latest effort, the Netflix series “Ratched.” Directed by frequent collaborator Ryan Murphy, the show features Wittrock as Edmund Tolleson, the murderous adopted brother of the title character, Mildred Ratched, of One Flew Over the Cuckoo’s Nest fame.