Even Oscar Isaac, cool guy supreme, melts into a pool of nerd the moment a Star Wars movie cues up on a big screen.

“When those little blue letters come up and say, “A long time ago in a galaxy far far away …,’ your heart starts pumping and the Star Wars symbol comes on and the John Williams score starts,” says Isaac, whose hero pilot Poe Dameron returns in Star Wars: The Last Jedi (in theaters Thursday evening). "And immediately, all the emotions and memories from when you were a child boil up inside."

The blockbuster franchise weathered a tough year, from original Star Wars icon Carrie Fisher’s death late last December to directors falling in and out of the upcoming Solo: A Star Wars Story (out May 25) and Episode IX (Dec. 20, 2019), the culmination of the current trilogy that started with 2015’s The Force Awakens.

But all that goes away for devotees with a new film to spark excitement and speculation on where George Lucas’ long-running saga goes next. “They feel like they’ve had some ownership in the property, so the responsibility is enormous,” says Mark Hamill, who looms large in Last Jedi as aging Jedi master Luke Skywalker.

Secrets abound, of course, but writer/director Rian Johnson and cast members weigh on what you need to know going into Last Jedi and how it leads into the future:

Mark Hamill returns as Luke Skywalker in 'Star Wars: The Last Jedi.' (Photo: John Wilson)

Luke Skywalker is definitely the star of this show.

Johnson wanted to hew Last Jedi to what's come before — especially Force Awakens, which introduced Poe, lightsaber-wielding heroine Rey (Daisy Ridley) and former Stormtrooper Finn (John Boyega). But everything for Johnson started with the original trilogy and Luke, who helped defeat the evil Empire but 30 years later has exiled himself from his family and the Resistance fighting the powerful First Order. “No matter how different Luke’s headspace is,” the filmmaker says, “there had to be a gut check where I could check back in with my 10-year-old self and the Luke that he knew, and I had to at least be able to see the line between the two of them.”

Laura Dern stars as new character Vice Admiral Amilyn Holdo in 'Star Wars: The Last Jedi.' (Photo: David James/Lucasfilm)

The heroes are maybe not so good and the villains may not be wholly bad.

The Last Jedi is a film that’s “about the unknown,” says Laura Dern, who makes her debut as new Resistance leader Vice Admiral Amilyn Holdo. She adds that all the characters explore "the deepest questions that George Lucas first presented about the light and the shadow and the humanized part of good vs. evil. (Johnson) let us live in the gray.” She adds that one of Luke’s lines ties to the bigger picture: “This is not going to go the way you think.” Which makes the trailer hinting at Rey's temptation toward the dark side all the more intriguing.

Rey (Daisy Ridley) is one of many characters struggling with the death of Han Solo in 'Star Wars: The Last Jedi.' (Photo: Lucasfilm)

Han Solo’s death affects everyone, but the reflection will have to come later.

Harrison Ford's cosmic smuggler met an untimely demise in Force Awakens via the business end of a lightsaber wielded by son Ben, aka First Order enforcer Kylo Ren (Adam Driver). Johnson teases that Han's death “lingers through the whole movie and it’s a factor in everybody’s journey going forward.” Since Solo became a father figure to Rey, she is “obviously grieving,” Ridley says. “But she’s still trying to see the best in people.” (The jury's out on whether that extends to Kylo.) Not that our heroes have any time to mourn. "There isn't much time to sit down and evaluate what’s happened," Isaac says of our heroes in the Resistance. "They’re on the run and they’re in survival mode."

General Leia Organa (Carrie Fisher, left) gives an order to Resistance pilot Poe Dameron (Oscar Isaac) in 'Star Wars: The Last Jedi.' (Photo: Industrial Light & Magic/Lucasfiilm)

'The Last Jedi' will be a tribute to Carrie Fisher’s legacy.

It’s going to be impossible for fans to see her as Leia without getting emotional, Isaac says. Because Johnson has treated her final role in a “beautiful and graceful way,” Last Jedi is “an incredible tribute to her,” says Isaac, adding that her sequences are strangely prophetic. “There seems to be so much in the film, particularly surrounding her character, about loss and the future and the direction everyone goes in after she’s gone."

J.J. Abrams (right) returns to work with John Boyega and his 'Force Awakens' stars for 'Star Wars: Episode IX,' out in 2019. (Photo: Alberto E. Rodriguez/Getty Images for Disney)

J.J. Abrams is coming back!

Whatever happens in Last Jedi, the Force Awakens director returns to wrap everything up in Episode IX. (Abrams replaces Colin Trevorrow, who was ousted in September.) “He sent me an email that said, ‘I’m crying!’ and I sent him one back saying, ‘I’m crying, too!’ ” Ridley says of Abrams. And her co-star Boyega recalls being “pleasantly surprised. It’s cool — in a way, it’s him finishing off what he started.” Domhnall Gleeson, who plays the First Order’s General Hux, says Abrams brings “energy and detail and love” to Star Wars: “He knows it as well as anybody else but he’s also had the world shook up in the meantime by what Rian’s done with it. You’ll get the best of both worlds.”

Director Rian Johnson (left) works with John Boyega and Oscar Isaac on the set of 'Star Wars: The Last Jedi.' (Photo: David James/Lucasfilm)

But Rian Johnson isn't done yet, though.

The Last Jedi filmmaker has been tasked to create three new movies outside of the ongoing Skywalker saga. “Rian is basically going to be the new Lucas,” Ridley says. Johnson says he’s at “the very beginning of the beginning” with his trilogy but won’t be pulling from the “terrible” stories he thought up as a kid. “Inevitably, the Stay Puft Marshmallow Man (from Ghostbusters) makes an entrance. Screenwriter me has some notes for 10-year-old me,” Johnson quips. That said, Star Wars at its core is “not about how it looks, it’s about how it makes you feel as a kid, and that’s really the thing that matters. That’s the thing I’m going to try and get back to.”