Three’s a family in “Professor Marston and the Wonder Women.” (Annapurna Pictures)

The Reelist is a column featuring Kristen Page-Kirby’s musings on movies. To read Washington Post film critic Ann Hornaday’s review of “Professor Marston and the Wonder Women,” click here.

I have not seen any interviews with Luke Evans about his role in “Professor Marston and the Wonder Women,” but I’ve gotten pretty good at predicting what questions celebrities will be asked repeatedly during press junkets. I will bet you a lunch at Taylor Gourmet that Evans has heard plenty of reporters ask some variant of “So how much fun was it to make out with two beautiful women at the same time?”

Evans plays William Moulton Marston in the fact-based movie, which secondarily follows the invention of comic book icon Wonder Woman and primarily depicts William’s polyamorous relationship with wife Elizabeth (Rebecca Hall, dark-haired and all angles) and Olive Byrne (Bella Heathcote, angelically blonde and all soft curves). The three were partners beginning in the 1920s; after Marston’s death in 1947, Elizabeth and Olive remained together until Olive’s death in 1985. Outside the bedroom, the family dynamic is surprisingly traditional (well, traditional with a plus-one): William and Elizabeth work; Olive takes care of the kids (each woman had two of William’s children) and the house. Inside the bedroom it is seriously, surprisingly sexy.

Why surprising? Wouldn’t a threesome automatically be sexy? Throw in some lingerie and a little light bondage — what could be unsexy about that? Well, plenty. Typically, heterosexual sex in movies is a little routine. There’s some kissing. There’s a long panning shot of the woman’s leg. Maybe we get a glimpse of the guy’s butt. Depending on the rating, there’s a certain amount of thrusting and writhing, and then cut to the next morning, when she’s wearing one of his shirts while making breakfast.

In most movies that depict sex, the camera functions the way a straight man’s eye would. That pan up the leg is really not for the women in the audience; the token shot of the man’s butt is. Male desire is at the literal center of the frame, often in the form of boobs.

How “Professor Marston” writer-director Angela Robinson break the pattern of humdrum movie sex is both simple and innovative — the women’s desire for and enjoyment of sex is entirely independent of William’s. Oh, he’s there and enthusiastically participating, but their pleasure is not defined by his, nor is it exploited by the camera. It’s about enjoyment, not objectification.

When the (probably male) reporters inevitably ask Evans about how much fun it must be to have a cinematic threesome, their assumption is that the sex is primarily for him. He wants it; the women are there for it. I highly doubt either actress will be asked how much fun it was to occupy her corner of the triad; if anything, they’ll get leering questions about what it was like to kiss another woman.

Hollywood has long hesitated to show women’s sexual desire or pleasure in any setting outside what ultimately serves men, either those inside the story or those sitting in the theater. When it comes to the sex in “Professor Marston,” everybody’s into it equally, everybody’s having a good time, and everybody goes home happy.

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