Crisis on Earth-X, Part 1

Supergirl -- "Crisis on Earth-X, Part 1" -- SPG308b_0339.jpg -- Pictured (L-R): Emily Bett Rickards as Felicity Smoak, Danielle Panabaker as Caitlin Snow, Candice Patton as Iris West, Grant Gustin as Barry Allen, Carlos Valdes as Cisco Ramon, and Chyler Leigh as Alex Danvers -- Photo: Bettina Strauss/The CW -- © 2017 The CW Network, LLC. All Rights Reserved