The CW has released The Flash Season 4 finale promo, which you can watch in the player below. Titled “We Are The Flash,” the episode will air on May 22 and is described as follows:
“Team Flash gets help from a surprising ally in their battle against DeVoe (Neil Sandilands).”
David McWhirter directed the episode, which was written by Todd Helbing & Eric Wallace.
The Flash stars Grant Gustin as Barry Allen/The Flash, Candice Patton as Iris West, Danielle Panabaker as Caitlin Snow, Carlos Valdes as Cisco Ramo, Tom Cavanagh as Dr. Harrison Wells, and Jesse L. Martin as Detective Joe West. New additions for the fifth season cast include Katee Sackhoff as the villain Amunet Black and Hartley Sawyer as Ralph Dibny, aka Elongated Man.
Based on the characters from DC Comics, The Flash is from by Bonanza Productions Inc. in association with Berlanti Productions and Warner Bros. Television, with executive producers Greg Berlanti, Sarah Schechter and Todd Helbing.