Darhk enters H.I.V.E headuarters with Malcolm Merlyn and others demanding to know if Genesis is still on track. After getting their assurances, he goes off on a rant and kills Milo and the other woman who's in the room, and declares it's time to begin the final phase of Genesis.
Felicity and gang are investigating Milo's murder. Oliver tells everyone he got some help from Constantine on where to go for help to defeat Darhk. Says that everyone needs to stay put while he goes to Hub City for a couple of days to learn how to defeat the magic. Thea says she's going on vacation with Alex.
Diggle goes to the mobile safehouse and lets Lyla know what's going on. He tells her he doesn't like sitting around. She tells him she'll see what her agents can find, then sends him off for diapers.
Felicity visits Oliver as he's packing. She tells him she's going with him and that she's already booked their rooms.
Diggle is leaving a store with diapers when he gets and alert as to Andy's location. He follows the trail which sends him to an abandoned building. It's a trap. Andy is waiting for him. They have a shootout. Diggle chases, but Andy escapes.
Lyla calls Diggle to tell him that satellite picked up Andy's signal, but he tells her he already knows. She tells him to stop chasing him, that she'll send backup, but he tells her he's not waiting.
Oliver and Felicity are all dressed up and go into a fancy underground casino to find Esrin Fortuna. Felicity sits down to play blackjack.
Thea wakes up in a rented house alone. She looks for Alex and finds him downstairs making breakfast. On the table is a bottle of "multivitamins."
At the casino, Felicity gives a losing woman some chips. Turns out it's Esrin who introduces herself to them.
Diggle is chases Andy into a power plant, but gets knocked out. He's tied up and hung on the pipes. Andy tells him he needs to prep him for Darhk. They talk about family, then Andy stabs John.
Felicity and Oliver talk with Fortuna who takes them to a secret chamber in the back of the casino.She explains to them about the power of the idol, that it only channels power, not gives it. Darhk gets his power from death. The more people he kills, the more powerful he becomes.
In order to defeat Darhk, Oliver needs to channel the Light of the Soul. If he can channel the good, he can repel Darhk's magic, but if he has more darkness than light, all he'll do is make Darhk more powerful.
At Wayward Pines Lite, Thea is starting to notice that something is off. Her cell phone isn't working and everything seems "too perfect." It doesn't bother Alex, who tells Thea she's just stressed out and calms down.
Diggle is still alive. The soldiers take him down and he wakes up fighting. He overtakes Andy and cuffs him to a pole. he raises his gun, but doesn't shoot even with Andy egging him on. Then he leaves. Without Andy.
Back at the magical chamber Fortuna starts working with Oliver. She starts off slow and Oliver is able to combat the darkness. Felicity keeps interrupting with questions. Fortuna is tolerant, but shoos her away.
After passing his first test, she ups the ante a bit. He needs to focus on light inside of him. Instead, he has a myriad of dark flashbacks including Felicity returning the ring and Laurel's death. He can't fight the darkness.
Fortuna has no tolerance and basically tells Oliver there is no hope for him and leaves.
Thea is telling Alex she doesn't remember anything. Doesn't know where she's at and keeps hearing the same sounds over and over. Alex doesn't really care. He picks up his bottle of vitamins to pop a few. Thea is surprised he's taking vitamins and grabs for them knocking them over. It's Darhk's little yellow pillls. Thea wants to know where he got them. He tells her Ruva. She accuses him of drugging her and takes off.
Diggle is back at the safe house with Lyla. She is furious. He is injured. She tells him he needs to fight Andy the right way with justice. He tells her he can't kill his brother. He wants to change him.
Felicty and Oliver are discouraged and are having a few drinks at the casino. Oliver tells her that she brings the light. He's starting to have a pity party and she calls him out on it.
Darhk finds Andy chained up and congratulates him on a job well done. They accomplished their goal of placing trackers on Diggle to lead them to Lyla and Sara.
Lyla is fixing Diggle's wounds when the proximity alarms go off. Diggle starts thinking it was strange that Andy didn't kill him. The monitors show that they are being followed. Darhk's men begin their attack and firebomb the truck. She calls for backup, but Argus is tied up. Diggle tried to reach Team Arrow, but can't get hold of anyone.
John figures out that Andy placed a tracker on him.
Darhk stands in the path of the truck and uses magic to stop it. Lyla tells John to take Sara and escape. When Darhk opens the door, Diggle escapes via motorcycle. Darhk sends Andy and other soldiers after them.
Darhk is looking for Sara, but realizes she's gone.
Diggle comes to a dead end and is surrounded by soldiers when Felicity shows up in a van and knocks a few over. Andy runs. Felicity takes Sara as Diggle chases after his brother.
He grabs Lyla, digs into her arm, and just when it seems like she's gonna die, Oliver shows up.
Darhk is not happy and tells Oliver he's going to kill all of Oliver's friends.
Diggle catches Andy and holds a gun on him...again, but doesn't shoot him. Andy taunts his brother.
Oliver and Darhk are fighting, but Darhk overtakes Oliver and is killing him when Oliver summons the light and repels Darhk.
Lyla is down. Darhk is gone.
Andy continues to taunt Diggle. He calls him out for being a coward unwilling to do what's necessary to protect his own family. Diggle shoots him.
Oliver comes on the scene and Diggle tells him what happened.
At the bunker, Oliver asks Felicity about Thea, but she hasn't heard from her. He tells her he used light magic to fight off Darhk and credits Felicity's voice for helping him.
Diggle is visiting Lyla who is in recovery. He tells her about Andy, but lies, telling her he tried to grab his gun. Lyla remembers her arm and freaks out.
Everyone is at the bunker (except for Thea.) Lyla explains that Darhk took Rubicon which was implanted subdermally in her arm as it was the safest place for it.
Rubicon is a ballistic launch override protocol to prevent any country, including the U.S., from firing a nuclear missile. But, it also can be manipulated to control all the world's stockpile of nuclear missiles.
Diggle brings up Andy's talk about "Genesis." Lyla figures out that it's from the Bible and means a destroying and rebuilding. The team figures out that Darhk is going to destroy the world using Rubicon, but wonder what he'll use as his "ark."
Thea is running through the neighborhood when she comes across ghost soldiers. She can't escape. She's trapped inside a Wayward Pines like dome. This is apparently Darhk's ark.