ARROW TEAMS UP WITH LAUREL TO FIND THE MAN IN THE MASK: Oliver (Stephen Amell) is conflicted after Laurel (Katie Cassidy) reaches out to the Arrow asking him to investigate Sebastian Blood (Guest Star Kevin Alejandro). Oliver is unsure whether to believe her accusations against the man he has publically supported for mayor, but decides to trust Laurel. However, when the pair gets too close to the truth, Sebastian exposes Laurel’s drug addiction and has her arrested. Meanwhile, Roy (Colton Haynes) reveals his new super strength to Sin (Guest Star Bex Taylor Klaus) who wants to test out his abilities. Unfortunately, Roy isn't able to contain his rage once unleashed and almost kills a man. Back on The Island, Oliver is surprised when Sarah (Guest Star Caity Lotz) reveals a secret about Laurel