In November 2015, Kreisberg signed a multi-year deal with Warner Bros. Television, through which he would continue to develop new projects as well as remain the sole showrunner of The Flash, co-showrunner of Supergirl (along with Ali Adler), and executive producer on Arrow and Legends of Tomorrow.

[11] In July 2013, it was announced that Kreisberg, fellow Arrow co-creator Berlanti and DC Comics CCO Geoff Johns would be introducing Barry Allen during the show's second season, with the twentieth episode serving as a backdoor pilot.

[15] On February 26, 2015, it was announced that Kreisberg, along with Guggenheim and Berlanti, would write/executive produce a spin-off series featuring Caity Lotz, Victor Garber, Brandon Routh and Wentworth Miller as White Canary, Martin Stein, The Atom and Captain Cold respectively, for a potential 2016 premiere.

In it, a college-aged Helen Keller is given a device which allows her to see and hear and which increases her physical abilities, at which point she is hired to protect the President of the United States.

[18] On November 10, 2017, Kreisberg was suspended from his role as showrunner on The Flash, Arrow, Legends of Tomorrow, and Supergirl, after fifteen women and four men accused him of sexual harassment.

[4][21] In October 2023, Vanity Fair reported that Kreisberg had been arrested in March 2023 and charged with forcible touching following an alleged incident at a bar mitzvah in Westchester County, New York.