A chilly play comes to chilly life in David Cronenberg’s “A Dangerous Method,” a 100-minute peek into the complex relationship between Carl Jung and Sigmund Freud, the birth of psychoanalysis and the schism between these two giants that impacts psychotherapy to this day.

A filmmaker with a history of sexual violence (“Dead Ringers,” “A History of Violence”), Cronenberg seems like an odd choice for this fascinating piece of real history, based on John Kerr’s book and Christopher Hampton’s play. But Cronenberg spares us few of the gory details of the patient who brought the two fathers of psychoanalysis together and helped tear them apart.

And while the film has the usual emotional distance that is a Cronenberg hallmark, he’s still able to push boundaries and make this a thoroughly thought-provoking parable of modern sexuality, modern life and our still-evolving understanding of the mind.

It’s about the sex-obsessed Freud (Viggo Mortensen) feuding with the ethically challenged Jung (Michael Fassbender) over that one repressed, masochistic patient (Keira Knightley). In this history, her case proves both the utility of psychoanalysis and the pitfalls of therapists taking on patients with sexual hangups.

Keira Knightley plays Sabina, a Jewish Russian girl, with an Old Hollywood style of hysteria – shrieking, laughing, writhing, her eyes darting as she is brought to the Swiss clinic where Dr. Jung is testing out Freud’s theories in the early 1900s. Jung is stumbling into this, finding his way – sitting behind the patient (couches would come later), probing and questioning. Sabina’s mania subsides.

That prompts Jung to want to meet Freud, given a quiet inscrutability by Cronenberg’s muse, Viggo Mortensen. His Freud is sure of himself, guarded, self-righteous and just a little paranoid. He sees a medical and cultural world aligned against his theories.

The film treats them as men who could see the future (Jung, especially), from America’s eventual prominence as a place that accepted psychotherapy quicker, to the world war that Jung believes he sees in his dreams.

At only 100 minutes, the movie cannot help but give us only hints of each man’s theories and beliefs and where they came into conflict. The clash of Jewish and Protestant cultures the men embodied is introduced but abandoned.

There’s a lot of bloodless conversation, even in matters of the heart. Perhaps that is the point – that unraveling this mystery is the end of romance and the beginning of the breakdown of mores, morals and social strictures.

Pondering that as you leave the theater, you’d be hard-pressed to think of a filmmaker who has benefited more from that Freudian/ Jungian seismic shift than David Cronenberg.