Malcolm does his own dirty workThe Undertaking is about to begin, and it's time to tie up loose ends. The Dark Archer ruthlessly murders the scientists at Unidac labs, where the device was constructed. Oliver sees his mother's reaction to the TV news about the attack, and it doesn't take long to figure out there's some sort of connection.
Meanwhile, Moira is chilled by a threatening visit from Malcolm. He confirms her assertion that Walter is only alive because he didn't know anything about their operation. She tries to just focus on the fact that Walter is back with her and to ignore his coldness toward her, but she has to face facts when he presents her with divorce papers.
Extreme measuresPosing as Arrow, Diggle "kidnaps" Oliver and Moira. Oliver takes a few punches for the team, because his "torture" provokes Moira into finally confessing what Malcolm's plans are. She tries to explain that her husband's original partnership with Malcolm left her vulnerable after his death. She was only trying to keep her family safe. Like with Walter, however, this isn't enough of an excuse for Oliver to forgive her. When Digg cuts them loose, Oliver refuses to let his mother even come near him.
Hacking the bad guysFelicity tries to hack into the Merlyn company's mainframe to locate the device that will destroy The Glades, but the system is too sophisticated even for her. She needs to get directly in at the source. Oliver uses an appointment with Tommy as a ruse to help get Felicity into the corporate building, and Digg poses as a security guard so he can man the cameras and keep an eye on their hacker.
Oliver keeps his appointment with Tommy, telling him that Laurel makes her own decisions and she chose Tommy. Oliver's not going to take the blame for Tommy screwing things up with her. He leaves quickly so he can go and help Felicity escape from being discovered, but he gets detained first by Malcolm, then Thea. Luckily Digg manages to get to her in time and whisk her away to safety.
Roy on a missionBy spying on police, Roy and Thea have overheard Detective Lance's suspicions about Merlyn Global Group and the deaths at Unidac. When Oliver runs into Thea at the Merlyn building, she's forced to confess to him what they're doing. Oliver threatens Roy to stay away from the vigilante and keep Thea out of danger... or else.
Thea is stunned when Roy ignores that advice. He's still determined to find Arrow. He says, like her, he's lost someone before and he wants to train to fight like the archer so he can prevent it from happening again. When Thea tells him he's going to lose her by keeping up this quest, he tells her "better now than later," which he regrets the moment she slams the door behind her.
Love triangleOliver has an epiphany that when his father told him he had to save the city, what he really meant was preventing The Undertaking. Digg is surprised when Oliver decides he'll "hang up the hood" once this mission is complete. Impulsively, he decides he can have a life with Laurel, after all. Having earlier rebuffed her attempts to rekindle their romance, he now goes to her apartment to tell her he thinks they can be together.
They instantly embrace and start tearing at each other's clothes, conveniently in front of a window so Tommy can see them from the street when he arrives at Laurel's apartment. Obviously motivated by Oliver's earlier meeting with him, the look of pain and anger in Tommy's eyes lets us know that this is a betrayal Tommy's not likely to ever forgive.
Yao's sacrificeIn this week's flashback, Yao Fei tells his daughter and friends that he captured them to avoid Fyers "fire-bombing" the forest to take them out. He felt this was their only chance. We learn that Fyers plans to shoot down any planes entering China's airspace and cripple that country's economy as a result.
To protect his daughter, Yao goes along with taking the blame for the missile launches -- which will mask Fyers' involvement. Yao then manages to slip Oliver a knife that he can use to cut free. There's not a lot of time, unfortunately, since Fyers immediately shoots and kills Yao the moment he's completed his confessional video for the world. Now there's no reason to keep the other three alive.
Good guys in dangerFelicity finally discovers where the device is being hidden. Oliver leaves Laurel's bed to go after Malcolm, but he's halfway through his threatening speech to the villain when Digg informs him the destructive machine is gone. Malcolm coolly informs Oliver that when he discovered his computer system had been hacked, he decided to take precautions.
Oliver decides to put an arrow in him, anyway, but he's stunned when Malcolm snatches it out of the air. They proceed to do battle in the office, and once again, Arrow gets his butt kicked by the Dark Archer. It's Malcolm's turn to be shocked as he pulls back Arrow's hood and sees that it's Oliver.
This isn't the only danger the vigilante team faces. Detective Lance has been following some of the same clues all along, and his own techie is clever enough to have discovered Felicity's hacking attempts at Merlyn Globa -- and he's managed to identify her. We know who will be getting a visit from the detective next.
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