WARNING: The following contains spoilers for the Titans Season 2 episode "Rose," streaming now on DC Universe.

DC Universe's Titans quietly began rewriting the history of the team in the build-up to its second season, first in the casting of Drew Van Acker as Aqualad, and then in the trailer, which confirmed there had been an earlier incarnation of the group of young heroes, with a swanky headquarters in San Francisco. While a chunk of the season will undoubtedly be devoted to teasing out why the original Titans -- Robin, Wonder Girl, Hawk and Dove, and Aqualad -- disbanded, the second episode gives a nod to another DC hero who, in the comics, was an early member of the team: Roy Harper, aka Speedy. The question is whether this is just a wink to viewers, intended to flesh out this fictional world, or something more.

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The reference comes as Kory Anders (Anna Diop) and Donna Troy (Conor Leslie) are engaged in a classic buddy-cop trope, the stakeout. In the three months since the events of the Season 2 premiere, they've struck up a friendship, and an apparent partnership, back in Chicago. Stuck together in the back of the surveillance van, they bicker like old friends, about doughnuts, about music, about whatever. Their search for the supervillain Shimmer (Hanneke Talbot), who in the comics was a member of the Fearsome Five, hasn't been fruitful, leading Donna to doubt her source.

"I don't know, I'm starting to think Roy Harper's intel was wrong," Donna says before taking a bite of doughnut (not jelly-filled, much to her dismay). It's a passing reference, sure, but a potentially significant one.

Roy Harper is, of course, Green Arrow's former sidekick, but he was also an early member of the Teen Titans in the comics. The original members, Robin, Kid Flash and Aqualad, first appeared together in 1964, in The Brave and the Bold #54, and returned six issues later, with Wonder Girl among their ranks, as the Teen Titans. They gained their own title in 1966, with Speedy making several guest appearances, beginning with Issue 4, before officially joining the team in Teen Titans #19. He and Donna Troy later dated.

Although he wasn't part of the team in The New Teen Titans, the popular 1980 relaunch from which Titans draws much of its influence, Roy did help his friends fight the Brotherhood of Evil. He rejoined years later, and led another incarnation of the team as Arsenal.

But will we actually see Roy on Titans? If we do, it's unlikely to be anytime soon. Although the first season demonstrated the series has little difficulty introducing a lot of characters -- the main cast, Doom Patrol, the Nuclear Family, Hawk and Dove, Donna Troy and Jason Todd, for starters -- Season 2 already has a lot of balls in the air. There's Superboy and Krypto (and Cadmus with them), the original Titans, Doctor Light and his vendetta, Deathstroke, Rose, the Aqualad mystery, the upcoming introduction of Jericho, the abduction of Kory by someone from her own planet, and the probable return of Shimmer as an ally of Doctor Light.

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There's also the matter of The CW's Arrow having its own version of Roy Harper, played by Colton Haynes, but that seems of little consequence. Sure, Warner Bros.' character-usage policy is inscrutable (Batman can't appear on Batwoman, but he can on Titans; likewise, Arrow can no longer use Deathstroke because of film plans, but he's fine for Titans), but Arrow ends in January, so there would appear to be few obstacles.

Given that Titans appears to be using Marv Wolfman and George Perez's The New Teen Titans as a loose map, from the threat of Trigon bringing the team together to the vendettas of Doctor Light and Deathstroke to the kidnapping of Kory, there's always a chance that Roy's introduction will come somewhere down the road, sometime after Brother Blood's arrival. Maybe the series will save that for the Season 2 finale's post-credits scene.

Streaming now on DC Universe, Titans Season 2 stars Brenton Thwaites as Dick Grayson, Anna Diop as Kory Anders, Teagan Croft as Rachel Roth, Ryan Potter as Garfield Logan, Curran Walters as Jason Todd and Conor Leslie as Donna Troy, with Minka Kelly as Dawn Granger, Alan Ritchson as Hank Hall, Joshua Orpin as Superboy, Chelsea Zhang as Rose Wilson, Chella Man as Jericho, Drew Van Acker as Aqualad, Esai Morales as Deathstroke and Iain Glen as Bruce Wayne.

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