Never doubt the ingenuity of a true pervert. 22-year-old Joel Hardman of Birmingham, England is one of those perverts. His deviant fetish of choice is women using the toilet.

So Joel came up with a scheme to film women while they did their business at a shopping mall in Birmingham.

Joel disguised himself as a MANNEQUIN . . . he wore a mask that made it look like his face was made of Styrofoam and wore a wig on top of it . . . and hid in a stall in the women's bathroom.

He figured if any woman saw him, they'd just think that a store left a mannequin in the stall. Yeah, there's a little bit of logic missing there . . . but he was a pervert on a mission and clearly wasn't going to let the little details slow him down.

When a woman would go into the stall next to him, he'd slip his cell phone under the wall to try to get footage of her on the toilet. He did that to three women before someone finally caught him . . . and no, they didn't think he was really a mannequin.

Joel told the police he gets turned on by the sound of a woman on the toilet and, quote, "Yes, I've been a bit weird . . . it's good that you've caught me. Maybe now I'll stop."

He was charged with observing another person doing a private act for his own sexual gratification and could get jail time.