It goes without saying that "Star Wars: The Rise of Skywalker," the ninth and final installment in the core series of films colloquially known as the Skywalker saga, will be a smash success at the Christmastime box office. But what is far less clear is whether the epic capstone to the 42-year-old franchise can unite fans who were bitterly divided over the last episode, "The Last Jedi," and satisfy viewers who have spent nearly half a decade stewing over unsolved mysteries. Here's a look at some of the key questions hanging over "The Rise of Skywalker" ahead of its Dec. 20 premiere, including whether America's favorite doe-eyed green puppet will make a cameo appearance.

Who exactly are the Knights of Ren?

Director J.J. Abrams has confirmed the Knights of Ren, a gang of elite warriors apparently led by the surly villain Kylo Ren (Adam Driver), will show up in his new film. He has been mum about the role the masked knights might play in "The Rise of Skywalker," however, telling Esquire in November: "They’re best kept more mysterious than familiar, which is just to say there aren’t going to be a lot of scenes with them taking their masks off and hanging out and eating sandwiches."

The black-clad malcontents first appeared in "The Force Awakens" (2015), the first installment in the sequel trilogy, after Rey (Daisy Ridley) touched a lightsaber that once belonged to Luke Skywalker (Mark Hamill) and experienced a vision of six rain-soaked knights surrounded by slaughtered people. The knights did not appear in "The Last Jedi" (2017), but that follow-up film, written and directed by Rian Johnson, suggests they may be former students of Skywalker who turned against the Jedi master.

At least one of the television advertisements for "The Rise of Skywalker" contains a brief glimpse of the knights — looking not unlike the title characters of Akira Kurosawa's epic "Seven Samurai" (1954) — gazing out over a desert landscape.

How is Emperor Palpatine still kicking?

The first teaser trailer for "The Rise of Skywalker," released in April during a fan convention in Chicago, climaxed with a surprise sound effect: the cackling laughter of Emperor Palpatine (Ian McDiarmid), the grotesquely wrinkled villain of the original "Star Wars" films. The sprawling "Star Wars" fandom had long assumed Palpatine to be dead, ever since Darth Vader tossed the cloaked menace into the reactor core of the second Death Star in "Return of the Jedi" (1983), the third installment in the original trilogy.

The internet has lit up with speculation about the role Palpatine might play in "Rise" — and how he might have survived his (literal) fall from the seat of power. What if the dreaded emperor, who can also be seen looming over Rey and Kylo in the official posters for the new film, has been reanimated ... or cloned ... or drops by to say hello as a ghost? The third possibility is not without precedent: Anakin Skywalker, Obi-Wan Kenobi and Yoda showed up as "Force spirits" in "Return of the Jedi."

Who (and where) are Rey's parents?

"The Force Awakens," the film that introduced Daisy Ridley's headstrong scavenger-turned-rebel, left fans wondering if Rey was the daughter of Luke, making her an heir to a powerful Jedi lineage that stretches back to Darth Vader. But in a divisive storytelling move, "The Last Jedi" seemingly put those rumors to rest: Kylo Ren told Rey her folks were “filthy junk traders” who sold her off for drinking cash, abandoning her on the desert planet Jakku.

The core team behind "The Rise of Skywalker" has hinted Rey's parentage may still be up for debate, however. “The parents thing is not satisfied — for her and for the audience,” Ridley told Entertainment Weekly in an article published in November. "That’s something she’s still trying to figure out — where does she come from?" The actress later added, even more cryptically: "It’s not that she doesn’t believe it ... but she feels there’s more to the story."

It seems some "Star Wars" die-hards agree with Ridley's assessment, filling up Reddit and YouTube with theories that Rey could share a bloodline with Obi-Wan Kenobi (Alec Guinness in the original trilogy, Ewan McGregor in the prequels), Han Solo (Harrison Ford), and other legacy heroes. The title of the new film itself, as some have speculated, could be a hint that Rey really is linked to Luke after all.

Are we going to see Baby Yoda?

If you have spent any time looking at the internet over the last month, you have surely encountered images of "Baby Yoda," the pointy-eared breakout star of "The Mandalorian," a "Star Wars" spin-off show that streams on Disney Plus. If you have not got your fill of GIFs, plush dolls, TikTok musical appreciations and all-purpose Twitter memes, then perhaps "The Rise of Skywalker" will have more of the charming tyke, known of "The Mandalorian" as The Child.

Abrams and his production crew have not said whether Baby Yoda will rear his tiny head in "Rise," but the chances are not entirely far-fetched. "The Mandalorian" takes place roughly a quarter-century before the events of the sequel trilogy, which means Baby Yoda would be in his late seventies during the events of "Rise" — practically a young man for a species that can apparently live for hundreds of years. Is it possible the little guy will join the fight against the First Order? Tell, only time will.