Having spent the past four decades making one transgressive exploration of “the new flesh” (per 1983’s Videodrome) after another, David Cronenberg seems like the last director in the world who would ever be interested in a conventional famous-man biopic. Sigmund Freud and Carl Jung, however, represent kindred spirits of a sort, as their early efforts to fashion a map of the human psyche demonstrate the same obsession with aberrant behavior that animates Crash, Spider and A History of Violence. So it’s immensely disappointing that Cronenberg’s new film about the working relationship between these two titans of the mind, A Dangerous Method, fails to live up to its titular adjective. The real danger here is that the audience might be talked to death.

Granted, the movie opens with an arresting, vividly Cronenbergian flourish, as a young woman, Sabina Spielrein (Keira Knightley), is dragged onscreen kicking and flailing, in the grip of what appears to be some unholy amalgam of a seizure and full-blown psychosis. Finding her treatment unusually difficult—and his sexual attraction to her overpowering, despite his being married—Jung (Michael Fassbender) consults his famous mentor Freud (Viggo Mortensen), who’s clearly in the best position to determine how Freudian this screwed-up couple’s impulses are. As it turns out, Spielrein, once “cured,” has her own bold ideas about human consciousness; she influences both men and later becomes a psychologist in her native Russia.

All of this historical material no doubt makes for fascinating reading, but while Cronenberg’s film was in part adapted from John Kerr’s nonfiction account A Most Dangerous Method, its screenplay was penned by Christopher Hampton, adapting his own stage play The Talking Cure. And Hampton, who previously wrote Carrington (about painter Dora Carrington) and Total Eclipse (about poets Arthur Rimbaud and Paul Verlaine), specializes in stodgy, painfully verbose, ass-numbing costume dramas, of which this is just the latest.

All three actors work hard—Knightley, in particular, bravely risks ridicule by working her lower jaw harder than Billy Bob Thornton in Sling Blade—but the result is nonetheless turgid and lifeless, an endless series of text-derived speeches that function as thesis statements. Bring back the horrifying mutations.