When Ben Stiller's character Ted got his penis caught in his fly in There's Something About Mary, men around the world collectively shuddered, praying something so awkward and painful would never happen to them.
It seems unlikely, particularly if you're wearing underwear to shield the skin, but according to new statistics, getting penises caught in zippers is actually pretty common.
Almost 18,000 men and boys visited emergency rooms in the US between 2002 and 2010 for "trouser zip injuries to the genitals", according to new research from the University of California, San Francisco and the Children's Hospital of Philadelphia.
And Sydney man Michael, 29, knows exactly how it feels.
He was rushing out of the bathroom at work last year when he felt a painful rip.
"I'd just caught the edge and it was bleeding," he recalls.
"I freaked out but knew I had to deal with it on the spot. It was getting more painful and more painful, so I ripped the zip back open. The guys I worked with were pretty sympathetic and compassionate."
There was plenty of blood and Michael said it took a few days for the cut to heal.
"I didn't go to a hospital or doctor — more through embarrassment," he said.
"I do get myself into a rush at times — the whole thing happened through haste. Thankfully it hasn't happened again for 12 months."
What to do in an emergency
The Royal Children's Hospital has a guide for doctors who encounter this injury.
If it's trapped between the slider, doctors are advised to use "liberal application of topical anaesthetic cream" before easing the slider down.
If it's a more serious injury, where the zip has closed above the caught skin, doctors will cut the median bar of the zipper, which is the part at the top of the slider that joins the front and back plates of the slider. Once that's cut, the slider falls off and the zipper teeth can be separated.