The Disney+ series about Cassian Andor, a heroic rebel leader, is set five years before the events of “Rogue One” and sees the Star Wars universe come back down to Earth.

As its charisma-deficient last three films underscored, Star Wars needs a new Han Solo, and it tries to fashion one with Andor, a Disney+ series about Cassian Andor, the heroic rebel leader played by Diego Luna who was first introduced in 2016’s Rogue One: A Star Wars Story. Created and written by that film’s co-screenwriter Tony Gilroy, this 12-episode affair (premiering September 21) aims to put the grit and grime back into the franchise, as well as a bit of roguish magnetism courtesy of its title character, a shady me-first loner whose run-ins with the Empire stir in him a desire to use his talents for revolutionary good.

Like Harrison Ford’s iconic smuggler—at least, before George Lucas somewhat neutered him with 1997’s “Special Edition”—Andor is a man who shoots first. And like Solo, that penchant for prioritizing his own safety, no matter the cost, gets Andor into peril at the start of Andor, which takes place five years before Rogue One (and, as a result, Star Wars). On the planet of Ferrix, Andor visits a brothel in search of his sister, who like him hails from Kenari, and who we’ll later learn he abandoned as a child due to a combination of ambition and misfortune. What he finds instead are two belligerent and corrupt contractors for the Preox-Morlana corporate security force that governs this outpost on behalf of the Empire. When they pick a fight with him at the bar and, afterward, attempt to shake him down, a scuffle ensues that leaves one dead and forces Andor to make a ruthless, self-interested decision that has lasting consequences for his safety.

Decked out in a hooded rain jacket, and with his face covered in a scruffy beard and, following this encounter, a not-inconspicuous bruise, Andor resembles a ne’er-do-well with whom one should not trifle, and Luna embodies him with grim, composed determination laced with simmering anger and resentment. At least in the first four episodes that were provided to press, Luna evokes Andor’s severity and skill with aplomb, if not many other shades of his personality. A scavenger, thief, scoundrel and mercenary who appears willing to do whatever it takes to achieve his ends, regardless of Imperial law or other mortal threats that come his way, the character has a no-nonsense attitude that fits the downbeat material and is contextualized by flashbacks to a youthful incident that set him on his current path. Still, going forward, one hopes Luna is allowed to explore additional layers of Andor’s fury, resolve, and—fingers crossed—sense of humor.

In its early installments, Andor is definitely not funny. Affecting the dour tone of Rogue One, it charts the fallout from Andor’s disastrous skirmish, which is shrugged off by the victims’ boss but not by Deputy Inspector Karn (Kyle Soller), an Imperial true-believer who can’t let the murder of Preox-Morlana employees go unpunished. Before long, he’s on the hunt for a suspect from Kenari, thereby bringing considerable heat down on Andor’s head, this despite the fact that only a handful of people actually know his true origins. One of them is Maarva (Fiona Shaw), his surrogate mother, with whom he lives along with B2EMO, a stuttering droid—and the most charming new voice in this saga—which must conserve energy to accomplish its tasks. There’s also Bix (Adria Arjona), a mechanic with whom he shares some obvious romantic sparks—much to the irritation of Bix’s boyfriend Timm—and who he turns to for assistance in selling a Starpath Unit for credits that will help him escape Ferrix.

Andor gradually establishes not only its budding hero and his relationships, but the universe in which he operates. Gilroy takes advantage of his 12-episode order by spending time fleshing out this sprawling society, with references to long-ago battles, rituals and famous figures imparting a grander and deeper sense of this world’s multifaceted history and culture. From the brief sight of a town bell-ringer taking his duties comically seriously, to chitchat shared by passengers on a transport ship heading into Ferrix, to vast panoramas of the construction and scrap yards where spaceships are built and taken apart, this landscape feels like a living, breathing, aged civilization. Additionally contributing to that three-dimensional realism are environments that exude worn-down weight and creakiness. Gilroy relies on practical locations and effects instead of employing The Volume—the ultra-HD digital set that’s gained fame courtesy of Lucasfilm’s The Mandalorian and Obi-Wan—and it pays off, lending the proceedings a winning measure of rusty, rugged substantiality.

There’s not a lot of pulse-pounding momentum to Andor’s initial exploits, with things only kicking into something approaching high gear once he convinces Bix to help him peddle his stolen wares and she hooks him up with Luthen Rae (Stellan Skarsgård), a mysterious buyer who proves interested in Andor’s goods and, moreover, in Andor himself. Whether or not Luthen is a Jedi remains, for the time being, unknown, yet by the fourth chapter, he does reveal himself to be a cagey and cunning player with deep ties to the nascent rebellion and, also, to the halls of Coruscant political power courtesy of Mon Mothma (Genevieve O’Reilly), a regal senator secretly working to undermine the increasingly fascistic Empire. Skarsgård’s gravity is a welcome addition to the series, and so too is the participation of Arjona as the fiery Bix and, later on, The Bear’s Ebon Moss-Bachrach as one of the insurgents Andor partners with for a daring robbery mission on behalf of Luthen.

Reports are that, down the road, Forest Whitaker will reprise his Rogue One role as rebel commander Saw Gerrera, and Shaw’s part will undoubtedly expand as Gilroy’s story unfolds. For now, though, it’s a promising stab at bringing the franchise back down to Earth (so to speak), favoring compelling new characters and guerilla-warfare action over lavish, force-related mythologizing. Buoyed by Luna’s sturdy headlining turn, Andor has the sort of jagged, weathered spirit that’s been missing for too long in this far, far away galaxy—even if the jury is still out on whether Andor is truly worthy or capable of assuming Han Solo’s mantle.