A new description for the episode indicates that Snart will help his old friend Barry Allen transport a dangerous meta. You can read the synopsis for the episode, which will air on April 24, below.
THE FLASH“Fury Rogue”— (8:00-9:00 p.m. ET) (Content Rating TBD) (HDTV)
WENTWORTH MILLER RETURNS AS CITIZEN COLD — When Barry (Grant Gustin) needs help transporting a dangerous meta, he calls on a new friend for help – Leo Snart AKA Citizen Cold (guest star Wentworth Miller). Meanwhile, Cisco (Carlos Valdes) becomes suspicious of Harry (Tom Cavanagh). Rachel Talalay directed the episode written by Jeff Hersh & Joshua V. Gilbert (#419). Original airdate 4/24/2018.
Following his addition to the spinoff series DC's Legends of Tomorrow, Cold changed from his villainous ways into a full-blown hero. Though he sacrificed himself to save his friends in the first season, he’s managed to return several times via hallucinations and time travel. Recently, Snart returned to the show as Citizen Cold, a heroic version of the character who helped the heroes fight off evil Nazis in “Crisis on Earth-X.” Although Miller's contract has expired, he has expressed interest in reprising his role provided the "right story" comes along.
Airing Tuesdays at 8 p.m. ET/PT on The CW, The Flash stars Grant Gustin as Barry Allen, Carlos Valdes as Cisco Ramon, Danielle Panabaker as Caitlin Snow, Candice Patton as Iris West, Jesse L. Martin as Joe West, and Tom Cavanagh as Harry Wells, with guest appearances from Keiynan Lonsdale as Wally West and Hartley Sawyer as the Elongated Man