Warning: This Article Contains MAJOR SPOILERS!
Star Wars: The Last Jedi introduces several new characters to the Star Wars lore, and one of the most pivotal ones in the story is none other than "DJ" (alias), a code breaker played by Benicio Del Toro. DJ crosses paths with Finn and Rose, while the two Resistance fighters are desperately searching the Casino resort on Canto Bight for a code breaker that can hack the security on "Supremacy," the Third Order flagship of Supreme Leader Snoke.
DJ's entire thematic arc have to do with the cynical hacker-for-hire trying to impart on Finn that in a war, concepts like "good" and "bad" are foolish to cling to over ones like self-preservation and profit. With that in mind, it makes sense that the actual hidden meaning behind "DJ's" name only further reinforces the theme of his character.
According to the Star Wars: The Last Jedi Visual Dictionary (via CBR), Del Toro's character uses the alias of "DJ" as an acronym for the phrase "Don't Join." He actually has the motto stamped on the tin plate on his hat, to reinforce his world view that the big warring powers of The Resistance and First Order are both flawed, and not worthy of his dedication and passion.
As a passage from the book describes:
“He thinks larger causes are for fools, since society is just a machine looking to turn everyone into a cog. First Order, Resistance, or New Republic — it doesn’t matter where on the spectrum such a cause may lie; ultimately all are meat grinders that chew up their followers with the same disinterest.”
DJ's sermon to Finn that 'it's all just a machine' came at a big moment in The Last Jedi, as Finn, Rey, and Poe were all facing moments of truth, with darkness looming over them. Ultimately, the film seems to favor the message hope and rebellion over DJ's cynical opportunist view, but there will be a lot of fans who want to see more of "DJ" in the future.
Star Wars: The Last Jedi is now in theaters.