Colton Haynes has teased a return to Arrow. When Oliver Queen started his journey as a hero/vigilante, he was very determined to go it alone. Over time he began to accept help from John Diggle and Felicity Smoak, but even then he was generally reluctant to accept assistance from anyone else. So when Roy Harper became obsessed with helping him, Ollie did everything he could to protect the young man. Over time, he gave in and trained Roy, who became his sidekick, Arsenal. Eventually, Roy claimed credit for being The Arrow and faked his own death, leaving town in order to protect Ollie.
Since then, Roy has only been seen a handful of times. Once when Thea went to visit him in his new home in Monument Point, he left to save her from a life on the run with him, encouraged her to take his place on the team - leading to Thea wearing the Arsenal costume and becoming Speedy. And once when he returned to Star City after being blackmailed by The Calculator. While he is mentioned frequently, Roy has been gone since season four.
But it looks like he is coming back. After a fan tweeted to actor Colton Haynes about missing him and Roy on Arrow, Colton responded with a tweet of his own, promising that Roy will be returning soon.
Roy's coming back very soon ?
— Colton Haynes (@ColtonLHaynes) September 9, 2017
Since season six will begin airing next month, it seems likely that "soon" is referring to the upcoming season. The tweet is certainly vague; it does not say how long the return is for or what the context is. Still, Roy's presence was missed in season five, specifically when the actor was unable to return for the 100th episode, which featured several characters who had previously died or otherwise left the series. Roy's image was shown and an audio clip played, but it wasn't quite the same.
It is also worth noting that out of all of Oliver's living loved ones, Roy was one of the very few who was not kidnapped by Prometheus and brought to Lian Yu for the explosive season five finale. Prometheus went to great lengths to find all the people Ollie cared about both as Oliver Queen and the Green Arrow, even tracking down his ex-lover Samantha and their son William. But Roy - along with Rory/Ragman who is also returning this season - were both noticeable in their absence. Whether it was because Roy was gone so long, or hid so well is unknown.
Aside from his friendship with Oliver, Roy's return could impact a number of other characters. Thea certainly will be affected by the return of her ex-boyfriend, and since she is no longer a regular part of Team Arrow, perhaps that is an opening for Arsenal to return. There is also a lot of unfinished business between Roy and Slade Wilson, who is the reason Roy was poisoned with mirakuru - which in turn is the reason Roy once murdered a police officer. Slade is on a mission of redemption at this point, but whether Roy will be able to accept or trust him is a big question indeed.
The season six premiere of Arrow will air on the CW Thursday, October 12 at 9 pm.
Source: Colton Haynes