‘Professor Marston and the Wonder Women’ has a lot on its plate

Rebecca Hall (left), Luke Evans, and Bella Heathcote in “Professor Marston and the Wonder Women.”Claire Folger/Annapurna Pictures/Annapurna Pictures

“Professor Marston and the Wonder Women” has a lot on its plate — you can see it right there in the title. It says we’re going to get a biopic about the man who dreamed up Wonder Woman, with an acknowledgment of his academic credentials, and it also hints that his inspirations were multiple — that more than one woman went into the creation of Diana Prince, the character most recently portrayed by Gal Gadot in this year’s multimillion-dollar epic “Wonder Woman.”

About the only thing the title doesn’t tell you is that the movie’s a loving, sensitive exploration of S&M bondage techniques and polyamorous relationships.

Which, of course, makes it sound far more lurid than it is. In the playing, “Professor Marston” is both a breakthrough and fairly stodgy. It squarely obeys the rules of the biopic genre, with a central character narrating us back through the lives in question and expert attention to period dress and décor.

Yet its portrayal of William Moulton Marston (Luke Evans) and the two women he loved — there were more in real life, but never mind — is tender, loving, and open to anything that consenting adults choose to do behind closed doors. The movie feels a little like “Henry & June” (1990) with a lot less lyricism and a dash more kink.

Whatever it is, it’s not based on Jill Lepore’s 2014 prize-winning nonfiction account of Marston, “The Secret History of Wonder Woman,” which is a great read and highly recommended. A long-in-the-works passion project from writer-director Angela Robinson (“D.E.B.S.,” HBO’s “True Blood”), “Professor Marston” finds the Saugus-born title character ensconsed at Harvard University in the Roaring ’20s, giving lectures on psychology to enraptured Radcliffe students while his scholar wife, Elizabeth (Rebecca Hall) — arguably the more brilliant of the two — tilts at the hidebound college administration.

They were intrigued by the physiological manifestations of deception — the ways we lie and how it shows — and the couple came up with an early predecessor of the polygraph test that in the film is used for both dramatic and comedic effect. But Marston also had novel theories about human desire and destiny, how great existential safety could be found in being lovingly controlled and restrained. The Marstons lived his theories in both their daily lives, with the arrival of a young student named Olive Byrne (Bella Heathcote), and in the pages of the comic books William wrote.

Byrne is portrayed as initially dewy-eyed and prim; she turns out to have feminist birth-control pioneer Margaret Sanger for an aunt and definite ideas about women’s role in society. The three enter into an unconventional but mostly happy long-term menage a trois that, about midway through the movie, delves decorously into ropes-and-scarves territory. The neighbors are shocked, but the film successfully portrays the relationship as emotional, genuine, at times difficult to maintain, but ultimately quite happy. And when Heathcote’s Olive dresses up with a lariat and a dime-store tiara for some erotic play, you sense the pulsing hormonal subtext behind our Spandexed superheroes.

Some of us in recent years have bought young daughters reprints of the original “Wonder Woman” comic books hoping for empowerment stories and getting more than we bargained for: Daddy, why does the powerful heroine keep getting tied up with ropes and chains? The movie addresses the subject head-on through its framing narrative, with Marston grilled by Josette Frank (Connie Britton), head of the Child Study Association of America, while various grim-faced minions (including Boston-area musician, writer, and character actor Tim Jackson) look on.

But while “Professor Marston” convinces us that Marston consciously used “Wonder Woman” to advance his ideas about gender and psychology — and there’s some rich comedy to be found between his high-minded approach and the low-down realities of the comic-book business — Robinson doesn’t have any attitude toward the kink of early “Wonder Woman,” good, bad, or indifferent. It’s just there, a byproduct of a man (and two women) who lived bravely, idealistically, and just the slightest bit naively.

It doesn’t help that Evans, an excellent actor who’s magnetic in villainous and supporting roles, doesn’t quite have the individuality to stamp Marston with the larger-than-life persona he was said to have had. Evans is fine but he’s overshadowed to some degree by Heathcote and definitely by Hall, whose Elizabeth Marston transforms over the years from a stiff-necked firebrand to an erotic author of her own desires, all while holding on to her feminism and her femininity. She’s perhaps the secret superheroine of this story centered on a more famous man. But it wouldn’t be the first time that’s happened.

★ ★ ½
PROFESSOR MARSTON AND THE WONDER WOMEN

Written and directed by Angela Robinson. Starring Luke Evans, Rebecca Hall, Bella Heathcote. At Boston Common, West Newton, suburbs. 108 minutes. R (strong sexual content including brief graphic images, language).