A seemingly impossible robbery at Queen Consolidated’s Applied Sciences Division brings Central City police scientist Barry Allen to town. Citing a similar case back home, Barry offers to help Oliver and team with the investigation. Oliver senses there is more to Barry than meets the eye, but he’s distracted by the similarities between this current case and something that happened on the island. Meanwhile, Felicity takes a liking to Barry, which doesn’t go unnoticed by Oliver. Sin asks Roy for help when a friend of hers goes missing. Roy is surprised when Thea not only encourages him to help, but joins the search. Unfortunately, Sin’s friend is connected to Brother Blood, and their search ultimately gets one of them seriously injured.
Elenco: Stephen Amell , David Ramsey , Katie Cassidy , Willa Holland , Paul Blackthorne , Emily Bett Rickards , Echo Kellum , Colton Haynes , Rick Gonzalez , Juliana Harkavy , John Barrowman , Susanna Thompson , Manu Bennett , Colin Donnell , Josh Segarra , Sea Shimooka , Ben Lewis , LaMonica Garrett , Katherine McNamara , Joseph David-Jones , Stephen Amell , Summer Glau , Susanna Thompson , Sussana Thompson , Willa Holland .