The fourth season of the American television series The Flash, which is based on the DC Comics character Barry Allen / Flash, follows a crime scene investigator with superhuman speed who fights criminals, including others who have also gained superhuman abilities. It is set in the Arrowverse, sharing continuity with the other television series of the universe, and is a spin-off of Arrow. The season is produced by Berlanti Productions, Warner Bros. Television, and DC Entertainment, with Andrew Kreisberg and Todd Helbing serving as showrunners.
The season was ordered in January 2017, and filming began that July. Grant Gustin stars as Barry, with principal cast members Candice Patton, Danielle Panabaker, Carlos Valdes, Keiynan Lonsdale, Tom Cavanagh, and Jesse L. Martin also returning from previous seasons, and are joined by Neil Sandilands.
The fourth season began airing on October 10, 2017, on The CW.
