Season 4 (The Flash)

The Flash was renewed for a fourth season by The CW on January 8, 2017. It premiered on October 10, 2017.

Main cast

 * Grant Gustin as Barry Allen/The Flash and Barry Allen
 * Candice Patton as Iris West
 * Danielle Panabaker as Dr. Caitlin Snow/Killer Frost
 * Carlos Valdes as Cisco Ramon/Vibe
 * Keiynan Lonsdale as Wally West/Kid Flash
 * Neil Sandilands as Professor Clifford DeVoe/The Thinker
 * Tom Cavanagh as Dr. Harrison "Harry" Wells, Harrison Wolfgang Wells, H. Lothario Wells, Wells 2.0, Wells the Grey and Eobard Thawne/Reverse-Flash
 * Jesse L. Martin as Detective Joe West

Recurring Cast

 * Danielle Nicolet as District Attorney Cecille Horton
 * Mark Sweatman as Norvok
 * Kim Engelbrecht as Dr. Marlize DeVoe
 * Dominic Burgess as Ramsey Deacon/Kilg%re
 * Patrick Sabongui as Captain David Singh
 * Jessica Camacho as Cynthia/Gypsy
 * Donna Pescow as Dr. Sharon Finkel
 * Richard Brooks as Warden Gregory Wolfe
 * Sugar Lyn Beard as Becky Sharpe/Hazard and Professor Clifford DeVoe/The Thinker
 * Danny Trejo as Josh/Breacher
 * Hartley Sawyer as Ralph Dibny/Elongated Man
 * Katee Sackhoff as Amunet Black
 * Chelsea Kurtz as Mina Chaytan/Black Bison
 * Kendrick Sampson as Dominic Lanse/Brainstorm and Professor Clifford DeVoe/The Thinker
 * Bill Goldberg as David Ratchet
 * Jessica Parker Kennedy as Mystery Girl
 * Derek Mears as Sylbert Rundine/Dwarfstar
 * Miranda MacDougall as Izzy Bowin/The Fiddler and Professor Clifford DeVoe
 * Bernadette Saquibal as Veronica Dale
 * Anne Dudek as Tracy Brand
 * Bethany Brown as Janet Petty/Null

Synopsis
"Running up against an evil time remnant version of yourself is something no one should ever have to do, but that’s exactly what faced Barry Allen (aka The Flash) as he fought to save the life of fiancée Iris West from the God of Speed known as Savitar."

"Barry’s victory was short-lived, however, as an unbalanced Speed Force began to wreak havoc on Central City, forcing Barry to sacrifice himself for the greater good."

"With The Fastest Man Alive now trapped inside an extra-dimensional energy, and unknown dangers lurking in the shadows, it will be up to Team Flash to free Barry from his own personal Hell."

Confirmed plot points

 * Tracy Brand will return at some point but she won't be a full-fledged member of Team Flash.
 * There will be a Cisco-Breacher story that doesn’t involve Gypsy.
 * The theme of this season is Fastest Man Alive vs Fastest Mind Alive.
 * Kevin Smith will direct episode 17.
 * Janet Petty/Null, Crucifer, and Edwin will appear this season.
 * The Mystery Girl's identity will be revealed later this season.
 * Breacher will return in.

Confirmed new characters

 * Janet Petty/Null: An accomplished jewel thief who has escaped capture for a long time. Has the ability to manipulate gravity. Sassy, but dangerous.
 * Crucifer: The leader of the Tenth Circle, Crucifer is a scarred brute who fights Breacher.
 * Edwin Goss: A hippie-type, Edwin has his life upended when he develops a power that makes him very hard to track.