'Star Wars: The Rise of Skywalker' stars reflect on filming the saga's conclusion and the lessons they learned along the way

The final installment of the 'Star Wars' saga will be released on Dec. 20.

Millions of people are eagerly awaiting "Star Wars: The Rise of Skywalker," the final episode of the blockbuster film saga to be released later this month. For members of the film's cast, it's a conclusion fraught with emotions.

"I don't think there was a day where I wasn't feeling very emotional," Daisy Ridley, who portrays Rey in the films, told ABC News’ Chris Connelly. "I don't think there were any easy scenes, because then, even the fun scenes were so out of the ordinary for me. I was like, 'Oh my god, we're having fun. Like how do I do this thing?'"

Forty-two years after "A New Hope" premiered, marking the start of one of the biggest movie franchises in history, the "Star Wars" saga will reach its long-awaited climax from director and co-writer J.J. Abrams.

Abrams, who also directed 2015’s "The Force Awakens," said it was important in this last film to hearken back to the history of "Star Wars" and connect it to the new narratives.

"How do we embrace what came before -- the familiar -- to tell a new story and go somewhere else? Because, if you look at this as nine films -- not a trilogy or even one movie, but say it's the end of nine chapters -- this chapter needs to connect all those that came before," Abrams told ABC News.

Watch the full story on "Nightline" TONIGHT at 12:35 a.m. ET

In anticipation of the new film, Abrams and the film’s cast members were given a sneak peek at the new “Star Wars: Rise of the Resistance” attraction in "Star Wars: Galaxy’s Edge" at California’s Disneyland Park ahead of its opening on Jan. 17.

Much of "Star Wars: The Rise of Skywalker" is expected to center around Rey's confrontation with Kylo Ren, who is played by Adam Driver.

In "The Last Jedi," Kylo Ren killed Supreme Leader Snoke and asked Rey to rule the galaxy with him as the new leader of the First Order. She refused, and in the new film, their struggle continues.

"Rey is still desperate for understanding her place in things," Ridley said. "She doesn't believe what she's been told. So there's a desperate search for where she comes from; what that means for her."

Ridley must again deploy her Jedi skills in the new film.

"I feel the anticipation," she said. "Every time J.J. says action ... genuinely, I have to move my mic because my heart is always pounding."

Fan-favorite John Boyega, who plays the former stormtrooper Finn, said he was happy to get screen time with his cohorts in the Resistance, some of whom weren't around while filming "The Last Jedi."

"It changes the entire movie when you're able to interact with people who you actually have a close relationship with in real life, and I just wanted the fans to see that real chemistry," Boyega said.

Last week, Boyega posted a cheeky video on his Instagram addressed to Oscar Isaac, who plays the fearless rebel pilot Poe Dameron.

In it, Boyega, with an exaggerated British accent, writes to Isaac about reflecting "on the adventures of Finn and Poe," saying, "I'm struck with anguish that John and Oscar have not been afforded the same caliber of companionship."

"I'm like, 'What is this?'" Isaac told ABC News with a laugh, adding that he was changing a diaper when he saw the video.

"That form of speaking, we kind of put on this voice and we talk to each other throughout the day in that way," Isaac said.

He called the "deep love" that he had developed in working with his castmates over the years as "rare and special."

The camaraderie poignantly amplifies Carrie Fisher's absence. Although Fisher died in 2016, Leia will live in "The Rise of Skywalker," Abrams said.

"The heartbreaking reality that she is no longer with us is so surreal," he continued. "Because, literally, she's been alive in the editing room every day for nearly a year, and the idea that we're sitting here talking about her in the past tense is still crushing and impossible to imagine."

In addition to Fisher's appearance in the new film, her legacy will live on with those she's worked with. Ridley, for example, spoke about how Fisher affected Ridley's understanding of "Star Wars" and its singularly devoted fans.

"Someone had asked her for a picture years ago," Ridley said of Fisher. "And she went to take a picture with them and their heart was beating really fast. And the thing [Carrie] said was, 'This really matters to people. Like, this is an important thing.'"

Abrams said he hopes the film gives people a sense of "transcendence."

"That feeling of getting to go somewhere that no other kind of movie will take you," Abrams continued. "You always feel safe in a 'Star Wars' movie, even when it's frightening, even when the story scares you. There's something about 'Star Wars' as a whole that I think has enormous heart."

"Star Wars: The Rise of Skywalker" will be in theaters Dec. 20.

The Walt Disney Company is the parent company of Lucasfilm and ABC News.