After Artemis betrayed the Green Arrow to side with Prometheus, Prometheus gained more ammunition against Oliver.

Prometheus was first introduced last month, but the real identity of his portrayer remains a mystery until now. According to "Arrow" executive producer Marc Guggenheim, "Arrow" season 5, episode 6 will finally reveal how long Artemis has been undercover for the new character. The executive producer also revealed that in Prometheus' final scenes with Oliver in the previous episode, that was when Artemis decided to be in Prometheus' camp.

Episode 6, titled "So It Begin," marked the first showdown between Prometheus and Green Arrow, according to Guggenheim. He said that it was in that same episode that the new recruits discovered that Oliver had actually crossed out their names, upsetting them. This was especially troubling for Artemis, who was already going through some bumps in her relationship with Oliver then.

It can be recalled that in between seasons, Artemis already joined Team Arrow again after forgiving Oliver. However, viewers saw towards the end of episode 6 that she cautioned recruits Wild Dog and Ragman not to trust Oliver because he was a serial killer.

While Artemis was fighting Prometheus on a subway, Oliver arrived. Prometheus disappeared and Artemis pretended to apologize to Oliver. Guggenheim revealed that Artemis' apology was just a façade, since she was already on the side of Prometheus.

The "Arrow" season 5 episode 9 aired on December 7, 8:00 P.M. on CW.