Millie Bobby Brown's fiancé Jake Bongiovi made quite a splash with his proposal. 

After all, the Stranger Things star, who announced her engagement to Jon Bon Jovi's son last April, recently shared how he popped the question during an underwater adventure. 

"We were on vacation and he was like, ‘Mil, you got to be up at 8 a.m. we're going on a dive,'" Millie explained to Jimmy Fallon on a Feb. 29 episode of The Tonight Show. "I was like, ‘8 a.m.? Dive?' and he's telling me, like, ‘We're going to the same spot we usually go to,' and I'm like ‘It's boring, let's go somewhere new,' and he's like ‘No, we have to go to this spot.'"

And while Jake, 21, was only trying to set up the perfect proposal—as the couple had bonded over the subaquatic activity—going under the sea for the big moment led to quite a few hiccups. 

"So we go under and we're like, many meters down and he gives me a shell and I turn it over and it's a ring," she continued. "And I looked at him, and he was like ‘Blurgh?'"

The Enola Holmes actress added that the couple could not speak underwater, but managed to communicate via hand gestures, and she showed Jake the ‘OK' signal to accept his proposal. 

As she put it, "I think it was underwhelming, but we freaked out."

In fact, the newly-engaged duo immediately ran into a major obstacle before they had a chance to resurface. 

"Anyways, he puts the ring on my hand and as I go to show him, the ring falls off my finger, plummets like so fast it was like a cinematic movie," Millie explained. "Jake throws himself so deep—the diver was like, ‘You can't do that, your ears, literally your brain will explode,'—he throws himself, he does a cinematic, like, grab, opens and saved the ring."

And for the 20-year-old, the heartfelt-if-imperfect proposal is emblematic of their three-year relationship. 

"I truly feel like it's a reflection of who he is," she declared. "I feel like we're always going to have each other's back and if anyone drops the ball, we got it."

As for the ring? Well, Millie would've had a back up no matter what—as Jake had planned to propose with her mother's ring, which she is now sporting, but did not risk taking it on their underwater expedition. 

"We got to the top and he was like, ‘Do you want to marry me?'" she finished. "He was like, ‘You know, I bought you this ring because your mom wouldn't let me take her ring'—she was like ‘Absolutely not Jake, you're not taking my ring, I know you'll drop it,' and she was right."

And while their engagement wasn't quite picture-perfect, Millie and Jake have shared plenty of adorable moments throughout their time together. Read on for all their sweet photos together. 

Jake shared a tribute to his partner for her 20th birthday, writing, "Happy birthday my beautiful fiancéI love you so much. Big year ahead."

The two appear at the event, where Millie was honored as one of two Global Women of the Year.

Jake shared this pic in the final days of summer 2023.

Millie and Jake enjoyed a day out with her sister Ava Brown, 11, and friends at the Six Flags Over Georgia theme park.

Millie announced the couple's engagement on Instagram, quoting Taylor Swift's song "Lover." The two would go on to celebrate with family and friends at an engagement party weeks later.

Jake marked Millie's 19th birthday on Feb. 19, 2023 with a sweet tribute, writing, "Another year around the sun together happy 19th to the girl of my dreams."

The sweet post included photos of the couple.

The pair's silly side is depicted in one image of Jake and Millie clowning around in the pool

Jake and Millie snuggle up in a romantic selfie.

Millie shared photos of the couple in celebration of the New Year, writing, "endlessly in love with the year I've had."

One snapshot showed a photo booth strip of the loved-up couple.

As Millie put it, "grateful for my friends, family, donkey (bernard), my doggies, my puppies teeth, and my partner for life."

Millie and Jake were twinning at the premiere of Stranger Things season four in New York City.

Millie and Jake make their first joint appearance at a celebrity event—the 2022 BAFTA Film Awards in London.

"We're starting a band," Jake wrote on Instagram, "send name ideas."

Jake posted this photo, with the caption, "bff <3"

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