In a dingy lab somewhere in China, a young girl named Wei (Mohan Liu) watches her father, Liu (Sam Wang), go about his work. He’s developing a new kind of skin graft procedure that he hopes will rid both of them of the large purple birthmarks adorning their faces. And like your average B-movie scientist with a little too much on the line, Liu decides to use himself as a guinea pig. He applies a strange, fleshy substance to his face and then grins triumphantly as it wriggles into life, replacing his birthmark and melding perfectly with the rest of his skin. But Liu’s delight quickly turns to horror as he discovers—like, well, so many B-movie scientists before him—that his invention works a little too well, and with deadly consequences.

Grafted is full of spluttering effects that look and sound wet and nasty, and they’re...