Automotive designers love hiding Easter eggs – little surprises tucked away in vehicles for no reason other than their own enjoyment… and ours. In most Opels, they take the form of a shark. Why a shark, you ask? Good question. And the answer is: for no particular reason.

As the story goes, one designer was tasked (as many are) back in 2004 with a rather mundane task. Namely, to design the outer panel for the glove box in the Corsa. Pretty boring stuff, so his son (innocently enough) suggested drawing a shark instead. So he did. And when he showed it to his boss, they actually put it into the production model. And so the custom started.

Years later, another designer hid three sharks inside the Zafira minivan. And then the Adam city car, the Astra hatchback, and the Insignia sedan. By now the automaker – once the centerpiece of GM’s European operations – has been taken over by PSA, but the custom continues.

They’ve put a few of them in the Crossland X and Grandland X crossovers, too. That covers most of Opel’s models, save for the Cascada convertible, Karl hatchback, Mokka crossover, and the Combo, Movano and Vivaro vans. (We can’t speak to the Cascada, but the Karl, Mokka, and the vans are made for – not by – Opel).

“I always encourage our designers to hide sharks in the interior in all new designs,” said the company’s interior design director Karim Giordimaina. “Because these small, but sweet Easter eggs stand for what distinguishes Opel: We are passionate about every detail of our interiors, fanatic in our pursuit for quality, but always in a fun, approachable way,” adding that “journalists ask us where the sharks are when we present new models.”

So if you’re looking to embark on a bit of an automotive Easter-egg hunt this season, and have an Opel in the driveway, just open the door and start poking around.