SPOILER ALERT: This story contains spoilers for “Treasure Protectors,” the season finale of “National Treasure: Edge of History,” now streaming on Disney+.

In the first “National Treasure” movie, Nicolas Cage’s Ben Gates justifies stealing the Declaration of Independence by telling the authorities he is a treasure protector — but that was so 2004.

In the Disney+ spinoff series “National Treasure: Edge of History,” the latest threat to this country’s lost history is from treasure destroyers, specifically a group known as Cras Est Nostrum (“Tomorrow is ours,” for those who didn’t take Latin). This faction hunts down and destroys treasure to avoid the messy business of having to rewrite history.

Billie (Catherine Zeta-Jones) and her specific brand of brute force has been the group’s muscle this season in pursuing Montezuma’s Treasure, which she calls a “political powderkeg” if found. And in this week’s season finale, she deciphers the final clue by kidnapping Jess (Lisette Olivera) and her father Rafael (Jacob Vargas), and dragging them through Louisiana’s treacherous Devil’s Swamp Lake –– where the Daughters of the Plumed Serpent hid the treasure 500 years ago.

But Billie has a reluctant co-pilot for the final leg of this hunt. In an eleventh-hour twist, FBI Agent Hendricks (Armando Riesco), who appeared in both “National Treasure” films alongside Harvey Keitel’s Agent Peter Sadusky, and has recurred on the series this season, reveals himself to be the nefarious Salazar, a generational title for Cras Est Nostrum’s wizard behind the curtain.

Armando Riesco, Catherine Zeta-Jones Courtesy of Disney+

It was Hendricks who poisoned Sadusky in the premiere, making it look like he died from natural causes, mere moments after delivering Jess the clue that starts the whole chase. From his post within the FBI, Hendricks has been actively dissuading the search for lost history since before he dismissed Ben Gates’ warning that Ian Howe (Sean Bean) would steal the Declaration in the original film.

Even in his retirement and battling dementia, Sadusky posed a threat to exposing the Pan-American treasure, something he ultimately still does before Hendricks shuffles him (and Keitel) off the “National Treasure” board for good.

Series creators Cormac and Marianne Wibberley, who also wrote the first two movies in the franchise, tell Variety the Hendricks twist was born out of early conversations about how to bridge the films and the series with something more consequential than a fleeting Easter egg.

“He’s the guy Sadusky turns to in the movies and says, “Now do you find it credible?” after the Declaration has been stolen,” Cormac says. “It was the perfect set up for us to reveal that he never reported it on purpose because of this larger conspiracy.”

They had initially gone even further to implicate Cras Est Nostrum in the events of the films. A scene earlier in the season, in which Billie is confronted by a boardroom of financial backers, originally included dialogue that confirmed the group was also behind the search for the Templar Treasure in the 2004 film.

“We actually had something in there along the lines of ‘We can’t have another Templar Treasure,’” Marianne says. “And Billie responds, ‘That was Ian Howe’s fault, not mine.’ We tried to tie all that in, even though things always end up on the cutting room floor. But we did think about how if it was all rewatched, it would fit together.”

Despite generations of effort, Billie and Hendricks are bested by Jess, Rafael and Liam (Jake Austin Walker), who manage to outwit the treasure destroyers, solve a booby-trapped puzzle deep in the temple and save the Pan-American treasure. But the final price for the hunt was paid with blood.

Hendricks senselessly kills Billie’s wounded partner Kacey (Breeda Wool), leading a distraught Billie to kill him in turn and assume the mantle of Salazar. It would prove to be a short-lived reign, though, as even a bag of C4 and blind rage couldn’t secure Billie the treasure she’d lost everything to find.

That treasure, meanwhile, is as rich with history as promised, including priceless Meso-American artifacts that expunge La Malinche’s history as a traitor to her Aztec people. It also gets a proper debut with a museum exhibit, something the films never got to do with their treasures.

In the end, a handcuffed Billie leaves Jess with a parting message: “What you have done is going to cost lives.” Whether that haunting goodbye bears any truth — as well as the historical implications of the treasure and what it means for the people who found — are all on the table should the Wibberleys be granted a second season.

“It’s funny because we always go back to the title of the show, ‘Edge of History,’ which was a nod to the treasure being hidden and history being erased,” Marianne says. “But it is also a reference to the young adults on the edge of their own histories. Who are they going to be? What are they going to carve out for themselves? We want to pursue Jess’ career. Does she really want to be an FBI cryptologist after all, or is there something else? Is this what she was born to do, like Ben?”

While Disney+ hasn’t officially greenlit Season 2, the Wibberleys are already brainstorming the next hunt, which is teased in the final moments of the finale. As the Treasure Protectors (not their official name, though it should be) celebrate victory, Liam reveals his grandfather, Sadusky, left behind what sure seems like the first clue to a new treasure.

From left: Jacob Vargas, Lisette Olivera, Jake Austin Walker Courtesy of Disney+

As for what that treasure may be, or from what era of history it originates, the Wibberleys will only offer nuggets of insight for what could await Jess and company.

“Without giving anything away, we would love to go West and international,” Marianne says. “We went South for this show, but we have so much history out there. Even California has a ton of history.”

One thing they won’t be addressing is Page 47, the cliffhanger they left dangling at the end of the 2007 sequel, “National Treasure: Book of Secrets.” Pulled from the pages of the president’s book, the story on the page was of more interest to Ben Gates than even Area 51 and the missing Watergate tapes. But it remains a mystery a decade and a half later.

The series’ fourth episode brought back Justin Bartha’s Riley Poole from the films, who teased that he and Ben are still working to unspool the secrets of Page 47.

But the Wibberleys confirm they are exclusively focusing on the series now, and Page 47 will remain the jurisdiction of the films. They are not involved with any effort to make a third movie, which has yet to be officially commissioned by Disney; nor have they even seen a script since 2010, Cormac says.

Following his guest appearance on the show in December, Bartha told Variety he has seen a script for a third film, by most recent scribe Chris Bremner, and remains hopeful the film could happen.

With the “National Treasure” franchise enjoying more forward momentum than it has in the past 15 years, there are already efforts underway to make it so the films and series can co-habitat –– should both officially get future installments.

The Wibberleys say they have been in contact with the producing team for the potential “National Treasure 3” to ensure they don’t double dip on clues. Someone within Disney was even designated to read scripts for the series to make sure they didn’t encroach on possible big-screen storylines, and vice versa.

“We want to help each other, and we don’t want to steal clues from each other,” Marianne says. “There was a clue we wanted to use that they wanted to use in the third movie –– so we didn’t use it.”

But the Wibberleys do have one piece of advice for the scribes that will succeed them in the film corner of the franchise.

“The one thing we tell the film side is that they better answer what’s on Page 47,” Cormac says with a laugh. “It’s the one thing fans ask us about all the time. They want to know.”

Marianne adds, “And it has to be life-altering whatever it is because that’s what Ben Gates told us!”