5. The Secret Origin of Felicity Smoak

Complete story — includes the ending

A cyber terrorist attacks Starling City, threatening to shut down all the banks and set everyone at an even socioeconomic status. While Oliver and Roy attempt to keep peace on the streets, Felicity works to find the virus. She quickly discovers that she designed the unstoppable virus five years earlier. Her mother, Donna, shows up unannounced and the two have a falling out their differences. Felicity soon realizes that Donna was unknowingly sent by the cyber terrorist—revealed to be Felicity's ex-boyfriend Cooper Seldon —who then kidnaps them both. Using Donna as leverage, Cooper forces Felicity to divert a set of armored vehicles, carrying newly minted money, to their location. She secretly uses a smart watch Ray gave Donna to also contact Oliver, who arrives with Roy and Diggle, stopping Cooper and his team. Felicity reconciles with Donna. Roy begins having nightmares that he was the one who killed Sara. Meanwhile, Laurel continues to train with Ted and tells him the real reason that she is learning to fight. Thea buys a house using the money she inherited from Merlyn and convinces Oliver to stay with her.