Nothing wrong with a nifty horror show that evokes the early David Cronenberg of The Brood. Adrien Brody and Sarah Polley play Clive and Elsa, genetics researchers with an itch to move on from experimenting with animals and start incorporating human DNA – a major scientific and moral no-no that lures an audience to demand a yes-yes.

Elsa is the Eve who tempts loverboy Clive to take a bite out of her apple. That would be a human-animal embryo with a sting in her tail and a mind of her own. Elsa names her Dren ("nerd" in reverse), and then the creature starts developing fast. Clive and Elsa try to hide their splice from the world.

Brody and Polley perform way beyond the call of sci-fi duty, creating complex characters that draw us in. But they can't compete with Dren. Played as a child by Abigail Chu and as an adult by Delphine Chanéac, Dren morphs into a special-effects miracle, sexy and scary in equal doses. Before the film devolves into cliché, director and co-writer Vincenzo Natali creates a potent and provocative thriller about gender politics and human impulses that can't be reduced to a science.