The first season of the American television series The Flash premiered on The CW on October 7, 2014, and concluded on May 19, 2015, after airing 23 episodes.

The series is based on the DC Comics character Barry Allen / Flash, a costumed superhero crime-fighter with the power to move at superhuman speeds.

It is a spin-off from Arrow, existing in the same fictional universe, and was produced by Berlanti Productions, Warner Bros. Television, and DC Entertainment, with Andrew Kreisberg serving as showrunner.

Gustin is joined by main cast members Candice Patton, Danielle Panabaker, Rick Cosnett, Carlos Valdes, Tom Cavanagh, and Jesse L. Martin.

The Flash was picked up for a full season by The CW in October 2014, and filming took place primarily in Vancouver, British Columbia, Canada.

On July 30, 2013, it was announced that Arrow co-creators Greg Berlanti and Andrew Kreisberg, Arrow pilot director David Nutter, and DC Comics CCO Geoff Johns would develop a television series based on the Flash for The CW, and it would detail Barry Allen's origin.

Johns stated that the character of the Flash in the show would resemble his comic book counterpart, complete with his trademark red costume, and not be a poor imitation.

This allowed the creative team to flesh out Barry's story and his world on a bigger budget, as opposed to a backdoor pilot's constraint of incorporating characters from the parent show.

[80] In July 2014, Johns described the series as "the most faithful DC Comics adaptation ever... We've incorporated almost everything of the mythology into it and added a new backstory with S.T.A.R.

Gustin primarily focused on The New 52 series of comics, because he knew it would be difficult to read everything and he felt the New 52 was the closest to the show's "look and feel".

[87] On February 10, 2014, Tom Cavanagh was cast as Harrison Wells, with his role described as "a rock star in the world of physics and the mind and money behind Central City's S.T.A.R.

[67] Letscher was cast due to his previous collaboration with Kreisberg and Berlanti in the ABC television series Eli Stone.

[96][97] He had previously composed a theme for Barry Allen which was featured in Arrow's season two episodes "The Scientist" and "Three Ghosts".

However, Panabaker and Valdes appear in the Arrow episode "The Man Under the Hood" in their roles as Caitlin Snow and Cisco Ramon, respectively.

[107] Previous Arrow adversary William Tockman / The Clock King (Robert Knepper) was in the seventh episode.

",[71][112][113] while Amell and Doug Jones as Jake Simmons / Deathbolt appeared in the twenty-second episode, "Rogue Air".

[114] In early January 2015, The CW president Mark Pedowitz announced the intention to do a Flash/Arrow crossover every season, after the success of the first one.

Characters include Arrow, Flash, Arsenal, Black Canary, Merlyn, Captain Cold, Heat Wave, Firestorm, Ra's al Ghul, Reverse-Flash, and the A.T.O.M.

[117] The Flash was screened at the Warner Bros. Television and DC Entertainment panel at San Diego Comic-Con in July 2014.

It broke the previous record for the most-watched telecast held by the cycle 8 finale of America's Next Top Model in 2007 (6.69 million).

[154] In the United Kingdom, the premiere was the fourth highest-rated broadcast of the week and the eleventh of that month, with 1.53 million viewers.

The website's consensus reads, "The Flash benefits from its purposefully light atmosphere, making it a superhero show uniquely geared toward genre fans as well as novices.

[162] IGN's Eric Goldman and Joshua Yehl praised the show's premise and cast after viewing a press screening copy of the pilot.

Club gave the season a B+ overall, giving praise to the pacing of the plot, the performances of the cast and the special effects, and also pointing out the series' boldness to embrace its comic book influences, something that conventional superhero shows tend not to do.

[164] Weekly episode reviewer Scott Von Doviak gave consistently high ratings to the season and awarded the season finale a perfect A grade, calling the episode "richly satisfying" and also commending the show for "[capturing] the essence of its source material in a fun, light-on-its-feet way that few other comic book adaptations have managed."

He also gave high praise to the emotional value and performances of the cast, as well as the cliffhanger and multiple easter eggs found in the episode.

[165] The Flash was included on multiple Best/Top TV Shows of 2014 lists, ranking on NPR and Omaha World-Herald's (7th), and Film School Rejects' (10th).