In a move that perfectly blends heavy-metal bravado with pure romance, Metallica frontman James Hetfield has just pulled off what might be the most jaw-dropping marriage proposal in rock history — 30 feet underwater, surrounded by gentle giants of the ocean.

The 62-year-old “Enter Sandman” legend ditched the traditional candlelit dinner for a wetsuit, snorkel mask, and a handwritten waterproof sign that simply read: “Adriana Gillett — Will You Marry Me?” The moment unfolded during an intimate swim with whale sharks in the turquoise waters off Isla Mujeres, Mexico, on Friday the 13th — a date that turned out to be anything but unlucky.

His glamorous girlfriend, 45-year-old Adriana Gillett, shared the magical footage on Instagram hours later, captioning the carousel of underwater snaps with pure joy: “The BEST birthday trip surprise. Swimming with whale sharks on Friday the 13th with the most unique, special and romantic proposal a Pisces could ever imagine. In a sea full of fish, we caught each other. Thank you God for putting us together.”

The video shows Hetfield calmly treading water, massive whale sharks gliding past like living submarines, while he holds the sign steady with one hand and gives a thumbs-up with the other. Adriana’s reaction? She dropped her snorkel in shock, nodded frantically, and the pair sealed the moment with an underwater kiss that fans are already calling “the most metal proposal ever.”

The engagement caps a whirlwind romance that began in early 2023, just months after Hetfield’s 25-year marriage to Francesca Tomasi ended in 2022. The couple, who share three adult children — Cali, Castor, and Marcella — parted ways citing “irreconcilable differences,” but insiders say Hetfield’s long-documented battles with anger and alcohol played a major role.

In a raw 2017 interview with Joe Rogan, Hetfield had laid it all bare: “Losing my family — that was the thing that scared me so much. That was the bottom I hit. She kicked my ass right out of the house… I was living on my own somewhere. I did not want that.” He checked into rehab, got sober, and slowly rebuilt his life. Friends say meeting Adriana — a yoga instructor and ocean lover with a calming Pisces energy — was the final piece of his redemption arc.

“James used to joke that the only thing bigger than his riffs was his fear of losing everything,” a close band associate told us exclusively. “Now he’s swimming with 40-foot whale sharks to prove he’s ready to commit again. The guy who once screamed ‘Never Again’ on stage is now whispering ‘Forever’ under the sea.”

The symbolism isn’t lost on fans. Whale sharks, the world’s largest fish, are known as gentle giants — peaceful despite their size — mirroring Hetfield’s own transformation from the chaotic 1980s thrash-metal wildman to a calmer, more introspective 60-something rock icon. And for a Pisces like Adriana, proposing in their natural element feels almost fated.

Social media exploded within minutes. Lars Ulrich posted a simple drum emoji and the words “My brother finally found his rhythm.” Kirk Hammett shared a guitar riff written in the shape of a shark fin. Even former wife Francesca sent a classy public congratulations on her own Instagram, writing: “Wishing you both calm waters ahead.”

As for the newly engaged couple, they’re already planning an intimate destination wedding — rumoured to include a small Metallica acoustic set on a beach at sunset. But first, there’s the small matter of eight explosive shows at Las Vegas’ Sphere this October.

Metallica’s residency, dubbed “M72: Sphere Edition,” kicks off October 1 and runs through Halloween with a twist fans are losing their minds over: no two nights will be the same. The band has promised completely different setlists every Thursday and Saturday, pulling deep cuts, new arrangements of classics, and even fan-voted rarities. Tickets sold out in under 11 minutes when they dropped last week, with resale prices already hitting four figures.

Hetfield himself hinted at the personal significance in a quick video from the shark swim: “I used to think the only way to feel alive was on stage with 80,000 people screaming. Turns out swimming next to a 30-ton fish holding a ring in my hand feels pretty damn alive too.”

From rehab rock bottom to underwater “I do,” James Hetfield’s second act is proving louder — and deeper — than anything he’s ever played before. Metallica fans, get ready: the master of puppets just tied the knot with destiny.