We meet Grant Gustin as Barry Allen on this episode of Arrow.
A man breaks into Queen Consolidated. A very strong man who can do the bidding of a handful of regular men.
When Oliver brings Moira to Queen Consolidated, Isabel angrily points out that her presence will not be well received by the community.
Barry Allen meets the gang.
The surveillance video shows the man who broke into Queen Co. was wearing a mask.
When Barry and Felicity introduce themselves, Oliver cocks his head inquiringly to one side.
Flashback: Shado is not impressed to learn Sara was on the boat with Oliver when it went down, as she is Laurel's sister and Oliver told her she was in love with her.
Oliver decides to throw a party for Moira to welcome her back to Queen Co.
Barry thinks that the Vigilante being green is indicative of his training and that he trained in a forest or something and that the green is a nod to that.
Barry is interested in the Vigilante because they never caught the person who killed his mother when he was 11. Maybe the Vigilante would have.
Sin goes to Roy when her friend goes missing in the hopes that maybe The Arrow could help. Thea offers Roy's help and then to go along with him.
Malcolm pays a visit to Moira. He explains to her that his guilt over betraying his wife is what drove him to Nana Barbat, and their encounter made him the man he is today. He demands Moira tell Thea the truth soon.
The truck used in the Queen Consolidated break-in is used to rob a blood bank.
Oliver asks Diggle to look into Barry Allen, as he believes there is more to the kid than meets the eye.
Oliver tells Felicity and Diggle about what he encountered on the island that was similar to the man they are seeking now. He talks about Dr. Ivo experimenting on men and enhancing endurance, strength and more. Oliver is certain all of the subjects and Dr. Ivo are dead.
Flashback: Oliver, Slade, Shado and Sara find the submarine.
Barry is very excited that the Vigilante is working the same case as they are.
Felicity invites Barry to the Queen Consolidated party as her plus one.
Roy, Thea and Sin look for someone who disappeared at the same time as a blood drive, and Brother Blood tells his minion they should find him.
Barry thinks it's exciting about the particle accelerator.
Oliver tells Barry he knows he's only an assistant who's bosses don't know he's in Starling City and that there isn't a similar case in Central City. He also notes that Barry's father was murdered by his father.
Barry accounts the night of his mother's murder, when a blur came into the house like a tornado and his father tried to fight it. When he tried to get to his father, he found himself 20 blocks away and that's why he looks into cases that seem unique.
Not many people show up to the Queen party.
Oliver makes sure Barry is at the party to dance with Felicity.
Isabel tells Oliver she tried to warn him, and he says he tried to ignore her. They do shots and Moira tells Isabel Oliver is a good son, but not the best judge of character.
Flashback: On the submarine they find the drug and Oliver wants to give it to Slade to save him.
Barry's boss calls him and he needs to get back to Central City or lose his job. He and Felicity say goodbye.
Sin and Roy find Max's body, and the police say he ODed. However, as a blood donor he couldn't have been using.
Felicity tells Oliver that his arrows cannot penetrate the man they are after.
Flashback: Oliver gives the serum injection to Slade.
When Roy goes to The Arrow for help, he tells him to stay away. Roy says he has friends who will help is Arrow won't and they can't be stopped.
Arrow says he can slow him down and pierces an arrow through Roy's leg.
Malcolm goes to Moira. He set her free and her life belongs to her. She tells him he will never set foot in her house again and won't go near Thea. He brags that the Vigilante couldn't even kill him. She admits that was true, but she knows who can. Ra's al Ghul. Moira threatens Malcolm with the
League of Assassins.
The man who broke into Queen Co. fights The Arrow and says he is merely a follower of his brother, who saved him with the miracle serum.
Flashback: Slade appears to die on the submarine just before Dr. Ivo arrives.
Oliver was injected with some sort of poison, and Diggle wants to call 911. Felicity refuses. They drug Barry and bring him back to The Arrow's lair.
Felicity asks Barry to please save her friend.