In this episode, Prometheus makes his move, using intel provided to him by Evelyn. He uses the intel to attack Curtis and his husband Paul, hospitalizing Curtis. It is revealed that Prometheus managed to inject Curtis with a specific vaccine. The team learns that Prometheus knows who they all are and will most likely come after them all. At the hospital, Curtis tells Paul that he is Mr. Terrific, which leads Paul to make Curtis choose between him or the team. The rest of the team locate Prometheus' hideout and go after him. Oliver and Prometheus battle, while Diggle and Renee manage to find them. With Prometheus surrounded and out-numbered the fight seems to be over. But Renee is disarmed by Evelyn, who reveals herself to be working with Prometheus. The two escape and the team return to the Arrowcave, distraught at Evelyn's betrayal.
The team learns that the vaccine originally manufactured by a company owned by Justin Claybourne, a man whose name was on Oliver's list from S1. In the flashbacks, we learn that Oliver went after Claybourne, who raised the prices on the vaccine when the sickness it would cure began to devastate a town. Oliver warned Claybourne to reduce the costs and help the people. Claybourne didn't heed Oliver's warning, causing Oliver to hunt down Claybourne, leaving a trail of bodies in his wake. Upon confronting Claybourne a second time, it is revealed that he released the virus to make money. Oliver then murders Claybourne and leaves.
In the present Billy investigates Prometheus, ending up getting kidnapped by the villain. Before he is taken, he manages to text Felicity a baby picture he found in Prometheus' hideout. The team originally suspects Prometheus to be Justin Claybourne, but it is revealed that he is actually Claybourne's son. The team learns that Prometheus has kidnapped Billy and Oliver goes out to rescue him, alone. Oliver tracks Prometheus to the facility where he killed Justin Claybourne. Once there, he finds bodies posed identically to the bodies he left in his wake four years before.
He finally confronts Prometheus who taunts Oliver. The two fight and end up int he building. Prometheus tells Oliver how he is the dangerous one and everyone he cares dies. Prometheus jumps out from behind a mirror, and Oliver puts three arrows in him. Upon approaching the body, Oliver notices that the sword is taped to Prometheus's hand.He removes the mask and finds that he has killed Billy instead of Prometheus. Oliver returns the Arrowcave, devastated, and tells the team what happens. Felicity blames Prometheus for Billy's death, and Oliver tells the team that they would be safer if they got away from him. The team surrounds and comforts Oliver who weeps. Oliver visits Susan Williams and opens up to her about his concerns. The two share and drink and kiss.The episode comes to an end with several cliff-hangers and emotional scenes (listed in the review).
After this episode, I have a reinvigorated confidence in Arrow. After the un-compelling S4 mid-season finale, I was concerned for this year's winter finale. This season has been fantastic so far. The Tobias Church story was interesting and fun while having the darker tone that made S1 and S2 so good. This episode is no exception. It keeps the viewer on their toes throughout and delivers some devastating blows toward the end.
We see most of the team get directly affected by Prometheus's plot. Oliver is tricked into killing Felicity's boyfriend Billy, Diggle is caught by the government, Curtis's husband leaves him, and Evelyn has gone rogue. All of these events happen almost in a complete succession of each other, giving the viewer no time to process each event before getting hit with the next one.
The most noteworthy event of the episode has to be the return of Laurel Lance. This will definitely be the most talked about reveal for the next month while fans ponder the nature of Laurel's return. Considering S4's biggest folly was killing off the favorite fan character, it is good to see her back. Despite what many people believe, not that many characters have truly come back from the dead. The only character so far who has been dead and buried and been brought back to life has been Sara Lance. Every other situation has involved near death experiences, time travel preventing the death, or being the Reverse Flash.
Another brilliant bit of writing is the fact that we are told exactly who Prometheus really is and, despite this, he is still a mystery to us. He is shown to be very intelligent and very skilled. He is almost a Deathstroke/Merlyn hybrid character; bringing in the best traits of the S1 and S2 villains. He is sure to up his game with the second half of the season and cement himself as Arrow's greatest villain.
This episode gets high praise and deserves it. I have high hopes for the rest of the season and if it is as good as these first episodes have been, then Arrow will have reclaimed its place at the top of the Arrowverse.