SANTA CLARITA, Calif. – Oh, the places (and centuries) they've been.

In just two seasons, the time-traveling heroes of NBC's "Timeless" have dropped in on the American Revolution, the 1893 Chicago World's Fair, a World War I battlefront in France and many other historical eras and locations.

The sci-fi, action drama, which was canceled in May, will visit two continents over three centuries in its two-hour, Dec. 20 finale, which will answer the show's outstanding questions, including many raised in the Season 2 cliffhanger.

The existence of the unusual two-hour closing episode is evidence of intensive fan efforts – including a second consecutive No. 1 finish in USA TODAY's Save Our Shows poll – to save a low-rated show that nevertheless enjoys a supremely devoted audience, whose rabid fans are known as Clockblockers.

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Just a few feet away from the iconic, time-jumping Lifeboat ship, USA TODAY asked the show's stars for their favorite episodes on the set of the two-part finale. Their choices (feel free to debate):

Abigail Spencer, who plays historian Lucy Spencer, picked two episodes: Season 1's "Last Ride of Bonnie & Clyde" and Season 2's "Mrs. Sherlock Holmes."

For Lucy and soldier Wyatt (Matt Lanter), her Lifeboat companion, the first episode shows "their relationship and love being reflected in these renegades," Bonnie and Clyde. "But I just thought the look of it, top to bottom, was everything I love about the show. You get a bit of history, a bit of romance, a bit of shoot 'em up, and you learn something and you get to fall in love on the other side of it. I love that (episode), aesthetically and as a story."

On a deeper, historical level, Spencer picked out Season 2's "Mrs. Sherlock Holmes," which chronicles the early 20th-century campaign for women's suffrage, for its revelations about important accomplishments that contemporary viewers may not know well. The episode features real-life historical figures Grace Humiston, nicknamed Mrs. Sherlock Holmes for her sleuthing skills, and Alice Paul, a suffragette leader.

"I learned so much during that episode," Spencer says. "And just to be marching through the streets of Los Angeles at Paramount Studios with hundreds of women and their banners and getting the right to vote. Really, the only way to change our future is to dissect the past and see what our grandmothers did and realize that we have a lot more to do."

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Lanter and Goran Visnjic, who plays former adversary and current Lifeboat-team ally Flynn, each cited the same episode, Season 1's "The Alamo," but for different reasons.

Lanter marvels at the physical creation of the legendary Texas mission. "We were in Vancouver, and we literally built an Alamo in the parking lot. And it looked completely different (from the surroundings). We had a dusty, dry, yellowy-looking episode and Vancouver was just not that.

"It also was a big episode for Wyatt," he says. "We (learned) a lot about the character. That's where we first got to know him."

For Visnjic, a personal memory stands out from that episode.

"My favorite scene was in 'The Alamo' episode where Flynn is actually speaking Spanish to General Santa Anna," he says. "It was my big achievement, because I don't actually speak Spanish. But I like to say I'm a good faker. I worked really hard on that scene."

Maybe too hard. After the show aired, "I got all these people on my Instagram starting to write to me in Spanish. And I would say, 'Guys, I don't speak Spanish,' and they would just ignore me, completely not believing me. They thought I was teasing them."



