The origins of Wonder Woman prove even more startling than her comic-book capers in Professor Marston and the Wonder Women.

Professor Marston and the Wonder Women quad Luke Evans Rebecca Hall Bella Heathcote

Gal Gadot’s Wonder Woman gave the superhero genre a zesty girl-power boost last year. But who knew the iconic comic-book heroine’s origins were quite so bizarre?

We are not talking about her Amazonian beginnings on Paradise Island, strange though those undoubtedly are. What is really far-out is the ménage à trois that inspired the character’s genesis in early-1940s America, as this eye-opening biopic starring Luke Evans, Rebecca Hall and Bella Heathcote makes clear.

Evans plays William Moulton Marston, the Harvard psychologist whose academic ideas and feminist ideals fed into his creation of the Wonder Woman comic – as did the polyamorous relationship he enjoyed with his wife Elizabeth (Hall) and their mutual lover Olive Byrne (Heathcote).

Professor Marston and the Wonder Women Luke Evans Rebecca Hall Bella Heathcote

Erotic sparks.

We first encounter the trio in 1928 at Radcliffe, Harvard’s sister college, where William is expounding his theories of sexual submission and dominance to audiences of wide-eyed female students, while Elizabeth, a brilliant psychologist in her own right, chafes at the chauvinistic restrictions placed on her career.

When William hires attractive student Olive as his research assistant, it’s no surprise that the atmosphere is sexually charged, but as things turn out the biggest erotic sparks are the ones struck between Olive and Elizabeth.

Writer-director Angela Robinson, maker of cheeky lesbian spy spoof D.E.B.S. and Disney’s Love Bug reboot Herbie: Fully Loaded, shows this unconventional relationship sowing the seeds for the comic book Marston began writing in 1941. His invention of a prototype lie detector kindles the super-heroine’s fabled ‘lasso of truth’, and her costume emerges out of the trio’s penchant for role-playing and bondage. Yes, a decidedly odd and kinky tale, but in Robinson’s hands a touchingly sweet and playful one, too.

Certificate 15. Runtime 108 mins. Director Angela Robinson