While the focus of “Arrow” Season 5 has definitely been on Prometheus (Josh Segarra), there’s another villain roaming the streets of Starling City. Vigilante has made a bad habit of getting in Oliver’s (Stephen Amell) way — and the Green Arrow’s way for that matter — all year, but no matter how often he shows up, we’re no closer to unmasking him.

According to executive producer Marc Guggenheim, that’s a mystery for Season 6.

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“We know who it is, but we were kind of intrigued by the idea of having a mystery that led into the next season,” Guggenheim told us at Paleyfest 2017. “We were excited at the prospect of just letting this play out for a little while longer, and it gives us something cool to do in Season 6.”

While we’re obviously bummed that this new villain will remain percolating in the background, we’re excited at the possibility of searching for clues about his identity. Especially when you factor in that under the visor, he’s apparently a character we’re already familiar with.

“As a general rule, I’m not a fan of mystery characters who when you take off the mask the audience goes, ‘What a minute, I’ve never seen that person before in my life,'” Guggenheim jokes. “I’m probably not spoiling anything by saying whoever’s underneath the Vigilante mask, you’ve seen that person before.”

All we really know about Vigilante is that he’s got no problem killing people he thinks deserve justice, and he’s likely lost someone very important to him. He chastised the Green Arrow for not being extreme enough, saying he must not have lost anyone if he was able to be as merciful as he is to criminals. Basically, he’s Season 1 Oliver with guns.

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So far, we can rule out quite a few people based on who and who hasn’t been present when Vigilante has attacked.

Obviously, all of Team Arrow is cleared, having traded blows with Vigilante at one point or another. The fact that Prometheus recently threw Vigilante off a roof rules out the theory that Adrian Chase could be both villains. For a while, we figured Susan Williams (Carly Pope) might be masking her identity with that voice-modulator, but her presence at Oliver’s press conference during Vigilante’s latest attack rules her out too.

The one character who’s never shared the screen with Vigilante? Curtis’ (Echo Kellum) husband, Paul (Chenier Hundal).

On the surface, Curtis and Paul’s breakup seemed to be because of Curtis’ decision to become a vigilante himself. Paul couldn’t handle the lying or the fact that Curtis was putting his life in danger every night. If you dig a little deeper though, you can find a pretty bonkers conspiracy theory that Paul is actually under that Vigilante mask.

Still, we don’t know if Paul’s sweet disposition fits very well with this merciless killer who considers Oliver’s tactics to be “too soft.”  There’s always the theory that it could be a character from Oliver’s past, but for now, we’re going to have to hope that Paul rules himself out eventually just like the rest of the current cast.

“Arrow” airs Wednesdays at 8 p.m. ET/PT on The CW.

Posted by:Lindsay MacDonald

Lindsay MacDonald is a Los Angeles based entertainment reporter with an affinity for CW superheroes. She graduated from Pepperdine University with a major in Media Studies and a borderline unhealthy obsession with TV in 2012. She would much rather spend the day binge-watching ‘The Flash’ or sorting ‘Game of Thrones’ characters into Hogwarts houses than venturing outdoors. TV words to live by: “Never ignore coincidence. Unless, of course, you’re busy. In which case, always ignore coincidence.”