The term “Death by Chocolate” usually refers to a dessert recipe — chocolate cake served with chocolate ice cream, chocolate syrup, sometimes with chocolate brownies or chocolate candies or chocolate shavings on top. Chocolate, chocolate, and more chocolate. For most, Death by Chocolate seems like a wonderful idea. The Nazis agreed — but took the term more literally.

In 2005, the British intelligence agency MI5 released a treasure trove of documents and photographs of camouflaged equipment used up by Nazi saboteurs. Among the documents released was the item depicted above — a sketch of what seems to be an ordinary chocolate bar. But instead of containing nougat, caramel, or Rice Crispies, these chocolate bars contained a bit more punch. This unique brand of Nazi chocolate were rigged to explode.

The chocolate bars were more akin to hand grenades than the confections they purported to be. They were steel-encased explosives covered with chocolate, all wrapped up in a candy bar-like wrapper. To detonate the bomb, the operative (or would-be victim) would break off the first row of “chocolate,” revealing a canvas strap. The strap worked like the pin in a hand grenade; once it was removed, there would be only a few seconds before the bomb would explode.

The likely target of the chocolate? Gizmodo states that the Nazis envisioned the British Royal family falling prey to the ruse, opening up a bar of chocolate only to find a very rude — and deadly — surprise. According to the BBC, while explosives camouflaged as food were found on Nazi agents in Turkey, none made it to the UK. However, four similarly constructed cans of peas, en route to Buckingham Palace, did make it to Ireland before being intercepted.

Of course, it’s incredibly unclear as to why the Nazis believed that a member of the Royal family would be opening up their own cans of peas.

Bonus fact : Say or hear a word over and over again, and it may lose its meaning to you. Almost all of us have experienced it, and you may have experienced this after reading the first sentence of the first paragraph above. (Your brain, after a while, may have been unable to center in on the meaning of the word “chocolate.”) This happens due to “a psychological phenomenon in which repetition causes a word or phrase to temporarily lose meaning for the listener, who can only process the speech as repeated meaningless sounds,” as explained by Wikipedia. The name of that phenomenon is “semantic satiation.”

From the Archives: When the Nazis Invaded America: Another Nazi saboteur plan that went awry.

Related: A fake chocolate bar that is actually a calculator.