The Dark Archer's appearance in Starling City has complicated Oliver's path. The new enemy was leaving a trail of dead bodies in his wake, setting things up so that the police thought Oliver, or rather Arrow, as he was now known, was the culprit.
Every night, he and Diggle scoured the streets of the city looking for any clue that would shed light on the Dark Archer's true identity while Felicity hacked into the city's surveillance cameras and databases in their hideout. All to no avail.
Soon, however, something completely unexpected happened.
"You've got to be kidding me." muttered Oliver, his gaze fixed on one of the monitors on which Felicity had opened a snippet of footage from one of the security cameras. "Another Archer? How can that be?"
"It's weird." She agreed. "But from the looks of it, he has the same goal as us - he's looking for a Dark Archer. I can find no other explanation for the fact that he's been following you like a shadow for the past few nights."
Oliver sighed, trying to gather his thoughts. He doesn't like what's happening, he feels that something has escaped his attention, something very important. But he needs to find the Dark Archer and stop him at all costs, even if he has to team up with a potential threat to do so. The enemy of my enemy, as they say.
"See if you can track down this new Archer." he finally tells Felicity. "We have no reason not to consider him a threat, but we need all the help we can get right now."