Ah, now it makes sense! That “internet mystery” was about an old-school puncture-style can opener—the kind your grandmother might have had in her drawer.
Before modern rotary and safety-wheel openers, these were essentially stabbing tools: you’d pierce the can lid with the point, then lever it open. They were incredibly effective but also dangerous, and many people have childhood memories of shredded fingers or bloodied knuckles trying to open a stubborn can.
So what looked like a “murder weapon” was just a relic of a time when kitchens demanded strength, precision, and a willingness to take small risks to get dinner done.
It’s a fascinating mix of nostalgia and horror: something so mundane now, yet back then, completely terrifying to use.
If you want, I can show a quick diagram of how it worked, so it’s crystal clear why people got so freaked out online.