What do you most look forward to after a relaxing dinner? In London, Guerilla Science serves a surprise scientific dessert activity. Atlas Obscura traveler and physician Lynn Eckhert shares a moment from London Science Weekend.

On our first night, while eating dinner upstairs at a pub, our guides announced a surprise dessert. They passed out masks, gloves, bibs, scalpels (knives), and little instruments for scooping. Then came the creamy pink gelatin brains on plates. They asked someone at each table to be the surgeon. At my table, I was the surgeon.

Lynn Eckhert preparing for surgery. Photo by Richard Eaton.

At the front of the room, a real neurosurgeon set up a table with his gelatin brain. A camera projected it onto a TV screen.

Like me, some of the surgeons who attended the event are real-life physicians. So when the brain projected on the screen was in reverse—like an X-ray—it wasn’t a problem to follow along.

Lynn Eckhert performing surgery on a gelatin brain. Photo by Richard Eaton.

The neurosurgeon explained the different parts of the brain—the frontal lobe, cerebellum, cerebrum, and brainstem—and what they do. Once you cut into the brain, you saw ventricles made with clear red gelatin.

We weren’t trying to get out a tumor or embolism or anything. We dissected the parts of the brain as the neurosurgeon described them.

In the end, you could eat the brain—they billed it as the dessert—but it wasn’t so attractive. You could slice it so that you got part of the brain and part of the ventricles, but no one wanted any.