Below Deck Mediterranean's Chef Johnathan "Jono" Shillingford is making a splash with his latest dinner menu in the worst way possible.

In E! News' exclusive sneak peek at the Bravo series' Aug. 26 episode, the season nine yachtie prepares a luxurious plate of tuna carpaccio with pineapple caramel for the new charter guests.

The only problem? One of the vacationers, Jennifer, is deathly allergic to the dish being served to her.

"It looks beautiful," she comments in the preview as everyone digs into the fish. "I would eat it if I could."

And when one of her friends asks why, Jennifer explains, "Because I can't eat raw seafood because it could kill me. In my preference sheet I said it about 15 times that I can't have it."

Though Jennifer is a initially a good sport about the mix-up, she's forced to tell Captain Sandy Yawn about the potentially fatal oversight when she checks on the guests during their meal.

"I would eat it if I could, but I have iron overload," she tells Sandy. "It might kill me if I eat it."

Needless to say, the captain is not happy and assures Jennifer, "I'm gonna handle that!"

In a confessional, a fuming Sandy adds, "What the f--k?! This is unacceptable."

The Captain then confronts Jono in the galley.

"One of the guests, it's on their preference sheet, raw seafood will kill her," she tells him. "And it's in front of her plate. That's a big screw-up."

Jono's reaction? "F--k me, bro."

See if Jono's mishap leads to a firing when Below Deck Med airs Monday at 9 p.m. on Bravo. And keep reading to look back at some of the wildest guest moments in Below Deck history.

The Bravo franchise has had plenty of dramatic and crazy moments thanks to some unruly and demanding guests, including Georgia, who was a little too flirty with no-nonsense leader Captain Lee Rosbach.

Sometimes, you just want a foam party—at least, that's what this demanding guest asked for. Was it eyebrow-raising to see him drunkenly partying in what ended up being about four inches of foam? Yes. Was it still epic because of how excited he was? Also yes.

Where do we start with Delores? The season eight Below Deck charter guest made a splash, literally and figuratively, after she drunkenly jumped into the ocean late at night. To make matters worse, this swimming session was in direct defiance to Captain Lee's order to stay on the boat. In a first for his career, Captain Lee ended Delores' charter early and sent her packing.

However, while being escorted away on the tender, Delores jumped into the ocean. Bold move, lady.

Barrie boarded the Parsifal III with his blended family, including his current fiancé and his ex-husband, in season two of Below Deck Sailing Yacht. With such a large guest list, the crew was certainly put to work, especially chef Natasha. Not only did Barrie have no problem sending his breakfast back, but he also refused to have his family served buffet-style.

The first charter of Below Deck season eight was certainly a memorable one. We're, of course, talking about when the charter guests found themselves bickering over deckhand James Hough. Specifically, charter guest Shay called dibs on the British yachtie. However, her boatmance hopes were derailed when pal Lexi flirtatiously rode a jet ski with James. Thus, a fight broke out over dinner, which shocked the Below Deck crew.

It was ladies night on the high seas in this episode of Below Deck Mediterranean, but as the drinks flowed, some of the women started to get a little handsy with deckhand Jack Stirrup. Thankfully, Captain Sandy swooped in to save the day.

The crew aboard this ship got a show they didn't ask for when two of the guests hooked up in the crow's nest, a part of the ship that everyone could see on camera.

In the same episode that the crew witnessed the on-deck hookup of two of their guests, they also discovered that their passengers also had never heard of cleaning up after themselves when they stumbled upon a used condom on the nightstand.

For the most part, the charter guest is always right. However, in season two of Below Deck Sailing Yacht, charter guest Erica requested that Captain Glenn Shephard do something to make the ship stop rocking. Unfortunately for Erica, they were in the middle of a thunderstorm and Captain Glenn didn't have the power to control the weather.

Other highlights from this charter group include a woman with hours worth of stories, bullying accusations among the ladies and so much more.

While many guests on Below Deck have been demanding, this may be the most ridiculous request because of how random it was. On one of the episodes, guests demanded gumballs, but not just any gumballs. They had to be colored gumballs and they even threatened to require they be delivered by helicopter if there were none on board.

Not every guest has found their trip to be a five-star experience, but usually they stick around to give feedback as to why. On this episode of Below Deck, we learn that a few of the guests straight-up ghosted upon arrival and fled the ship before even saying goodbye to the crew.

(E! and Bravo are both part of the NBCUniversal family)

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