There’s a moment in the latest teaser for Star Wars: The Rise of Skywalker that made me sit up and go, “Huh!” At the 1:20 mark, we see a fleet of Resistance fighters and capital ships drop out of hyperspace, and seconds later, we get a glimpse of a massive fleet of Star Destroyers. It looks as though the scene is teeing up a confrontation between the Resistance and the First Order, but when you look a little closer, something’s off — something that gives me vibes of one of the earliest Star Wars novels: Timothy Zahn’s Dark Force Rising.

When we see the fleet of Star Destroyers — dozens of them — they’re parked in rows, lights off. Moreover, these aren’t the hulking, Resurgent-class Star Destroyers that we’ve seen the First Order use in The Force Awakens and The Last Jedi. These look like the classic Imperial-class Star Destroyers of A New Hope, The Empire Strikes Back, and Return of the Jedi — ships that we’ve seen crashed in the deserts of Jakku, but were phased out in the years since the Empire fell. Cue the rampant speculation.

The Resistance was hit hard at the end of The Last Jedi. The First Order attack decimated its D’Qar headquarters, and pursuing forces chased them off into space, picking off their ships one by one until a final confrontation on a distant world named Crait. While Leia, Poe, Rey, and Finn, and a handful of their companions, were able to escape, no matter what they’d spend some time in the aftermath licking their wounds and looking to replenish their forces and allies. Two subsequent Star Wars novels, Black Spire and Resistance Reborn, promise to fill in the gap between the two films.

That fleet of Star Destroyers harkens back to another story from the Star Wars universe: Timothy Zahn’s famous, beloved, and now non-canon Thrawn trilogy from the early ’90s. Five years after Return of the Jedi, the New Republic has been largely able to take over the galaxy. But when Zahn picks up with the galaxy in Heir to the Empire, our heroes face a cunning grand admiral who uses his tactical genius to marshal the remaining, divided Imperial forces to restore the Empire. At the end of Dark Force Rising, the location of a lost fleet of Clone Wars-era warships — which have been sitting in the depths of space for decades, waiting to be recovered and put to use — threatens to tip the scales for either side.

The Katana Fleet was a force of 200 Dreadnought cruisers led by an advanced flagship, the Katana, which controlled the other 199 ships. Unfortunately, the crew of the ship went mad and jumped into hyperspace, where they became lost. When Luke Skywalker and Han Solo eventually got the location from a smuggler, they undertook an unauthorized mission to scout out the fleet.

At first all he could see was the normal scattering of stars, achingly bright against the total blackness around them. And then he saw them: the softer glow of a ship’s running lights. His eyes traced the empty space between them, his brain forcing a pattern to the lights; and suddenly the image coalesced. “It’s a dreadnaught, all right.” “There’s another one just past it,” Han said. “And three more to the port and a little below.”

The ships ultimately play a bigger role in the fight between Thrawn and the New Republic, and it makes for a very good story: a lost fleet, two sides desperate for supremacy, and a race to locate and/or put them to use.

Zahn’s Thrawn trilogy, like the rest of the pre-Disney novels, is no longer canon. But that hasn’t stopped Lucasfilm from recycling parts that it could put to use. Star Wars has notoriously embraced ideas, design concepts, and stories throughout its history, and three years ago, Grand Admiral Thrawn, one of the franchise’s best villains, triumphantly reappeared as the chief protagonist for Star Wars Rebels, complete with an origin story (and sequels) from Zahn himself.

Other elements of the Star Wars Expanded Universe been recycled as well: minor things like starships in Rebels (the TIE Defenders seen in the X-Wing novels, or the Quasar Fire-class Bulk Cruisers from The Truce at Bakura) and larger plot beats in the sequel trilogy, like Han and Leia getting married and having children, then one of the kids falling to the Dark Side. Chuck Wendig’s canon novel Aftermath: Life Debt drops in an interesting detail about a potential lost Imperial fleet: “Seventy-five percent of the Star Destroyers in service before Endor can capably be tracked to similar fates: destroyed, captured, lost in confirmable if curious ways. But a full quarter of those ships cannot be accounted for.”

This (sorry) fleeting glimpse of ships in this latest Rise of Skywalker trailer certainly isn’t proof that the film is drawing inspiration from Zahn’s nearly 30-year-old novel, but I don’t think it’s something that can be disregarded out of hand. The sequel trilogy has consciously updated its designs for everything from its stormtroopers to TIE and X-Wing fighters to Star Destroyers. Seeing the older Star Destroyers parked with lights out makes me think that they’re there more than just for a dramatic space battle. Whatever their role, we’ll find out on Dec. 20, when The Rise of Skywalker hits theaters.