Between the unremitting stream of AI slop, conspiracy theories, unsourced gossip, and deepfake videos, my patience for April Fools’ Day is at an all-time low. I’ve already trained myself to believe basically nothing I read or see on the internet without checking multiple sources, and here comes a whole day encouraging even more prankery. Enough. So my first thought when I woke up today and saw an alleged new watch from Swiss brand Nivada Grenchen—which features an automaton of two penguins exploring each other’s torpedo-shaped bodies on the caseback—I immediately dismissed it as a lurid prank and moved on.

But as it turns out, the joke is on us. I saw the new “Antarctic Erotic” enough times that I finally sent an email to the brand’s PR rep to confirm it wasn’t a joke. “No joke at all!” they wrote back. “But a good amount of humor.”

The very-real Nivada Grenchen Antarctic Erotic starts with a serious foundation. The Antarctic model is an identity touchpoint for the brand, which was founded in Grenchen, Switzerland, in 1926. The brand is best known for its assortment of rugged tool watches, and no piece is more emblematic of that ethos than the Antarctic. In 1954, the brand sent this model to Admiral Richard Byrd and his US Navy crew to wear on their Antarctica-bound missions, which were codenamed “Operation Deep Freeze I.” The watch had to be as tough as the Navy members: able to be thrown into icy waters and endure heavy snow.

It’s atop this bonafide expedition watch that Nivada Grenchen is exploring the full breadth of what those US Navy members might have come across on Operation Deep Freeze I. While the dial of this watch is all business (save for the mention of “Erotic” in small cursive type) it goes full Dirk Diggler on the back. Flip the watch over and you’ll find two cartoonish penguins smashing—an animation that actually comes to life when the piece is wound.

There is a surprisingly long history of sexy scenes showing up in watchmaking. There are erotic pocket watches that date all the way back to the 1600s, used for a range of reasons: a parlor trick perhaps, as satire meant to thumb the conservative ruling class, or for legitimate private use. Centuries before desperately horny folks could reliably resort to keeping a Playboy under the mattress, the horndogs commissioned skilled watchmakers to animate their fantasies.