“NCIS” dropped a bombshell Tuesday night — and this time, it wasn’t the explosive kind.

Warning: Spoilers ahead.

In one of its most brutal twists ever, the long-running CBS hit action drama killed off Rocky Carroll’s Director Leon Vance during its milestone 500th episode, leaving fans absolutely reeling.

“It is never easy to say goodbye to any of our characters,” executive producer Steven D. Binder told TV Insider. “But we wanted to honor Rocky and his legacy on the show as best as we could — in this case, giving his life so his agency could live.”

After 18 seasons, Carroll’s steady, commanding Vance met a shocking end — not in a blaze of glory, but in a cold-blooded betrayal.

The episode opened with NCIS itself in crisis mode, shut down amid a widening scandal. Vance refuses to back down, even with a bomb threatening to destroy key evidence that could save the agency.

But the bomb? A fake-out.

The real danger is standing right next to him.

The Army CID agent working alongside Vance is secretly part of a smuggling ring — the same conspiracy the reunited team has been investigating while trying to clear an innocent woman framed for murder in a case tied back to Gibbs’ (Mark Harmon) early days.

Then comes the moment that changes everything.

The agent turns — and shoots Vance.

For a split second, it looks like he might survive. The scene depicts Vance wearing a bulletproof vest and surviving the shooting.

However, it’s revealed when Vance is later speaking with an interrogator — who is later shown to be a younger version of Dr. “Ducky” Donald Mallard standing in for the Angel of Death — that he was fatally shot.

“There have always been real stakes,” Binder said, pointing to the show’s history of shocking losses. “Perhaps as best embodied by what happened to Agent Todd (Sasha Alexander) in the Season 2 finale.”

Carroll admitted he didn’t fight the decision to kill off the character that he had portrayed for nearly two decades. In fact, he embraced it.

“In the process of saving the agency, he loses his life,” he recalled Binder telling him. “It’s a great story.

“It was basically presented to me that the studio and the network wanted to do something really spectacular, really big, and something that would really send shockwaves through the NCIS fan base and the community.”

The emotional punch kept coming in Vance’s final moments, as he was guided toward death by Ducky, who plays Young Ducky on the “NCIS” spinoff “NCIS: Origins.”

“You don’t need a special reason to bring back Adam Campbell. The man is a rock star,” Binder said. “I happened to catch one of the Young Ducky episodes on Paramount+, and the moment I saw Adam’s face, I realized what it needed to be.”

By the end, the conspiracy unravels: the shutdown of NCIS was built on falsified numbers by a corrupt official. The agency is reinstated, the team returns, and Parker (Gary Cole) even comes out of retirement.

But the victory comes at a cost that can’t be undone.

“The team will be grieving, of course,” Binder said. “Vance died to protect them all. And they are going to honor that by putting one foot in front of the other, and just continuing on their mission to protect and safeguard their country.”

The message is clear: NCIS moves forward. Even without Vance.