David Cronenberg approaches A Dangerous Method with an air of cool detachment, akin to a therapist analyzing a patient. Though appropriate for a story about Sigmund Freud, Carl Jung and the development of psychoanalytic theory, the scholarly vibe limits the movie’s effectiveness. Viggo Mortensen, as Freud, and Michael Fassbender, as Jung, do a good job of sketching out the intellectual dance between mentor and increasingly skeptical student, while Keira Knightley froths and fidgets as a patient who becomes Jung’s lover and a professional disciple of both famous shrinks. Knightley’s performance is overly showy and the love story isn’t up to the task of giving this cerebral film emotional force. Cronenberg’s analysis of Freud, Jung and psychological philosophy comes off like an essay, brainy but lacking in heart and soul.