On tonight's episode of "Arrow," which was titled "So It Begins," Prometheus began his direct assault on Team Arrow. Up to this point, Season 5's main villain and threat had been Tobias Church, but when Church attempted to kill Mayor Queen in last week's episode, Prometheus killed Church. While Prometheus' motives were unknown, his agenda was clear: discredit, lure, and kill the Green Arrow. Oliver's quest to discover Prometheus' identity led him to two conclusions: Prometheus knows about Robert Queen's list and that he works at the Star City Police Department. These revelations came as Felicity studied the identities of the men and women Prometheus killed this week and his unique brand of throwing stars. Because of the danger that Prometheus presented to Team Arrow, Oliver decided to keep his new recruits in the dark. This secret keeping led to a team conversation about Oliver's past as the Hood, his previous propensity to kill, and whether or not he should be keeping secrets from them. This episode also revealed a startling revelation about Quentin Lance, which definitely changes his role moving forward this season. In the Russian flashbacks Oliver finally met his target, Konstantin Kovar, the formidable and "Rocky" guest star, Dolph Lundgren.

Once a Serial Killer

During their quest to find Prometheus, Oliver and Diggle tracked down Church's cell phone. The phone was a trap, which led them to the message, "So it begins." This fiery message signaled the start of Prometheus reign of terror, which began with randomly killing citizens of Star City. After Felicity and Curtis ran some tests of the names of these victims, they discovered these killings weren't random at all. They were anagrams for names on Oliver's father's List. Oliver put the List down in Season 1, after the Undertaking, when he realized the work of his mother, father, and Malcolm Merlyn could not be stopped. Felicity also did some research on Prometheus' silver throwing stars, after stealing one from her boyfriend's desk at the Star City Police Department. She discovered that the DNA and the metal alloy of the throwing stars came from Oliver's very own arrows -- potentially four years worth. This led Felicity to believe that Prometheus was obtaining Oliver's arrows from the evidence lockers at the police department. Only three characters on the show this season would have access to that evidence locker: Deputy Mayor Quentin Lance, Felicity's boyfriend Detective Billy Malone, and the new District Attorney Adrian Chase. So far Billy has shown no signs of hating the Green Arrow -- in fact when Felicity told him that she worked for the Arrow tonight he seemed enthusiastic. Adrian said a few weeks ago that he thought vigilantes were doing the work of the police department, so he could be Prometheus, but that wouldn't explain his knowledge of the List.

Off the Wagon

Lance is looking like the candidate with the best motive for being Prometheus, despite how far-fetched that sounds. Take for instance Lance's original tension with Oliver when he returned from the island. In the first few episodes of Season 1, Lance's main mission was to ruin Oliver's life because of the death of Sara Lance on the Queen's Gambit. Lance always hated Oliver, he even tried to expose Oliver as the Hood back in Season 1 and had been hellbent on bringing both Oliver and the Hood down throughout the entirety of the show. It wasn't until recently that Lance began to trust Oliver and forgive him for Sara's death. This change of the heart over the seasons doesn't change the evidence, however, as Lance woke up in a haze with his arm cut at the end of the episode. During Prometheus' fight with Artemis, she cut his arm pretty deep. Lance had a cut in the same place and seemed to have no memory of how he got the cut. Could he be suffering from a mental break? Lance has experienced the most tragedy on this show, both in the five years he thought Sara was dead, then when he lost Sara again, then again when Laurel was killed -- and technically all of those deaths can be linked to Oliver Queen. If Lance turns out to be Prometheus, whether knowingly or unknowingly, it will prove that -- from day one -- this show has been Oliver v. Lance, and it may finish that way.

Keeping Secrets 

Over the last few weeks the new recruits have each gone through their own personal gauntlet. Wild Dog was tortured last week and had to learn how to get back in the field. Ragman wanted to leave the team after Felicity confessed to killing his family, but decided to stay and work through his pain. Tonight Evelyn/Artemis had her Team Arrow trial, and it had to do with trusting Oliver. When she was looped into Oliver's vigilante past with the List, she was appalled that Oliver was technically a former serial killer. By executing the men and women on his father's List, Oliver was essentially working through a kill list. That was not was Artemis signed up for, and she had the opportunity to leave the team this week. She decided to stay, when Oliver apologized for not being honest with her about it, which was a huge step for him. In seasons past, Oliver's secrets have kept him from having meaningful relationships, mainly with Felicity, who left him last season after finding out he had a secret son. Oliver has clearly learned from that mistake and was willing to come clean with Artemis and the team moving forward.

The Rise of a New Vigilante

The episode concluded with Oliver and Felicity discovering that Prometheus was either working with or at the Star City Police Department, which cut to a scene with Lance finding Artemis' cut on his arm. According to the episode description of next week's episode, titled "Vigilante," Lance will confess a shocking secret to Thea. The flashbacks concluded with Oliver in Kovar's custody -- but not as a member of the Bratva -- as Oliver Queen. Perhaps Kovar will have mercy on him.

ARROW “Vigilante” — (8:00-9:00 p.m. ET) (TV-14,V) (HDTV) DOLPH LUNDGREN “ROCKY” GUEST STARS – When the bodies of two criminals are dropped at SCPD, Oliver (Stephen Amell) realizes there is a new Vigilante in Star City. The team is split about whether they should stop someone who is helping keep the city safe. Diggle (David Ramsey) is frustrated with his new situation and Thea (Willa Holland) fights for Lance (Paul Blackthorne) who confesses a shocking secret. Meanwhile, in the flashbacks, Oliver finally sits down with Konstantin Kovar (guest star Dolph Lundgren). Original air date 11/16/2016.

Starring Stephen Amell as the Emerald Archer, “Arrow” airs Wednesdays at 8 pm ET/PT on The CW. The series also stars Emily Bett Rickards, David Ramsey, John Barrowman, Willa Holland and more.