Updated on 17th March:



Arrow EP Marc Guggenheim revealed at a Monday press event that The Flash castmembers Danielle Panabaker (Shark, Necessary Roughness) and Carlos Valdes (from Broadway’s Once) both will guest-star in Episode 19 of the CW’s hit sophomore drama.Panabaker on the spin-off pilot plays Caitlin Snow, a bioengineering expert who lost her fiancé during the particle accelerator snafu at Central City’s S.T.A.R. Labs. (The smart money has her one day evolving into Killer Frost.) Valdes Carlos Valdesmeanwhile plays Cisco Ramon, S.T.A.R. Labs’ youngest genius (who may be fated to become the Justice Leaguer known as Vibe).“The idea of bringing in those characters really, really appealed to us because it allowed us to honor our original intention [of] doing something Flash-related around Episode 19 or 20 without … basically paying Grant Gustin to sit around with his eyes closed/unconscious the whole episode,” Guggenheim explained, saying that Barry won’t emerge from his coma until The Flash (presumably) premieres this fall. “This episode is really cool. It allows us to further flesh out the Flash universe on Arr