“The Acolyte,” the latest product off the Lucasfilm assembly line (it premieres Tuesday night on Disney+), enters territory unfamiliar to the casual follower of “Star Wars.” It is set during a prehistorical period known as the High Republic, until now depicted primarily in short stories, novels and comic books read only by serious fans. (The High Republic stories are to George Lucas’s central works somewhat as “The Silmarillion” is to “The Hobbit” and “The Lord of the Rings.”)

Moving a “Star Wars” story out of the main time stream — no Empire, no R2-D2, a century before Luke Skywalker — has not liberated it from the franchise’s oldest conventions and clichés, however. “The Acolyte” tweaks the formulas here and there, but, to a greater degree than other Disney+ shows like “The Mandalorian” and “Andor,” it falls back on signature moves: the electronic whoosh of the light saber; the outstretched hand summoning the Force; lovable droids and fuzzy holograms; dark masters and chosen children.

Created by a newcomer to the franchise, the writer and director Leslye Headland (“Russian Doll”), the show is focused on twin sisters in their mid-20s, Osha and Mae, both played by Amandla Stenberg. They share a tragedy in their childhoods that has left them with very different feelings about the Jedi knights, who in the High Republic time frame are comfortably ascendant across the galaxy, before their later tribulations in the “Star Wars” films.

That critical moment, revealed in the season’s first half (four of eight episodes were available for review), involves one of Headland’s more noticeable creations: a coven of witches who tap into the Force with a holistic, communitarian ethos. (They feel borrowed from an early episode of “Star Trek,” with a swerve into unintentionally hilarious musical theater when they perform one of their ceremonies.) The nature-principle witches and the power-principle Jedi converge, spawning a vendetta plot centered on the grown twins that allows for plenty of planet hopping action. The fights are copious, and in another new twist for “Star Wars,” many of them take the form of balletic martial arts face-offs.

But the storytelling force is not strong. Putting more female characters, and a stronger female point of view (even if it is sometimes redolent of 1960s earth mother), into an otherwise traditional “Star Wars” framework is worth the attempt. “The Acolyte” doesn’t bring enough energy or invention to the task, though.

It goes through its space-opera paces, offering some blandly pretty forest planets and the occasional impressive landscape. (Location shooting was done in Wales and Portugal.) The “Star Wars” penchant for paying homage to the backlot bazaars and gin joints of classic Hollywood is frequently indulged.

Beneath the familiar trappings, the visceral pull that “Star Wars” can summon in its best moments — “The Empire Strikes Back,” “The Last Jedi,” parts of “Andor” and “The Mandalorian” — doesn’t manifest itself. Characters speak in platitudes about loss, grief, loyalty and revenge, and the cast mostly works down to the level of the dialogue.

Stenberg is capable and charming but can’t make either twin very interesting; Lee Jung-jae of “Squid Game,” who plays a sympathetic Jedi, doesn’t make much of an impact in his first English-language role. The most winning performances of the early episodes are given by Lauren and Leah Brady as the 8-year-old Osha and Mae — the most winning performances by humans, anyway. In the “Star Wars” universe, robots tend to have as much personality as their flesh-and-blood co-stars, if not more, and Osha’s pocket-size droid, Pip, is a trouper. With proper maintenance, he might outlast the High Republic.