A version of the Flash guest-starred in the animated series, The Adventures of Aquaman in 1967. Flash appeared off and on in the Super Friends series throughout its run from 1973 to 1985. Flash appeared in Challenge of the Super Friends, Super Friends: The Legendary Super Powers Show, and The Super Powers Team: Galactic Guardians.
In 1979, he appeared in the live-action Legends of the Superheroes specials, played by actor Rod Haase.
The Flash's most famous villain in the series was the Trickster, played by Mark Hamill, which oddly foreshadowed Hamill's subsequent success at voicing the Joker in Batman: The Animated Series and, later, the Trickster in Justice League Unlimited. Captain Cold, played by Michael Champion, and Mirror Master, played by David Cassidy, also appeared in their own episodes. The complete series was released as a DVD set by Warner Bros. in 2006.
The Flash in the Justice League animated series is voiced by Michael Rosenbaum (Lex Luthor on the television series Smallville). This Flash is Wally West; however he is an amalgamation of Barry Allen and Wally (in Justice League Unlimited, Wally is a forensic scientist, which was Barry's profession. Wally in the comics is an auto mechanic). Michael Rosenbaum also voiced Kid Flash for a Fall 2005 episode of Teen Titans animated series entitled "Lightspeed". He later appeared in a cameo in the episode "Calling all Titans" and then he reappeared fully in the episode "Titans Together".
The importance of the Flash as the "heart" of the Justice League was shown in the episode "A Better World", when his death in an alternate timeline triggered a series of events which turned that alternate League (the "Justice Lords") into virtual dictators of Earth. He has also proven key in saving the day in a few episodes, such as Divided We Fall, in which he defeated the fused Brainiac/Lex Luthor when all the other six founding Justice League members could not. In the process, he was drawn into the Speed Force (the first explicit use of the concept in the DCAU), and barely managed to escape. The episode "Flash and Substance" is centered on the opening of the Flash Museum. Many of the Flash's rogues make cameos in this episode, while focusing on Captain Boomerang, Mirror Master, Captain Cold, and The Trickster (voiced by Mark Hamill). Linda Park also appears as a reporter covering the museum opening. Mirror Master alludes that Wally West may not have been the only Flash stating to the rest of the Rogues, "We've all been stopped by a Flash.
The Flash appeared at the end of The Batman's fourth season finale The Joining as one of the members of the Justice League. The Flash was properly introduced in the episode A Mirror Darkly to help Batman battle Mirror Master. Also Charlie Schlatter reprised the role of Flash from the above Superman episode Speed Demons. Creators stated that their version was intended to be Barry Allen, but they'd leave it up to the viewers to decide for themselves. He is more similar to Bart Allen in attitude, and personality.
The Flash made guest appearances in the television series Smallville, in the fourth-season episode "Run" (first aired October 20, 2004) and in the sixth season in the episode "Justice" (first aired on January 18, 2007). He is played by Kyle Gallner. He is portrayed as a self-centered teenager who uses his powers for personal gain. He goes by the name Bart Allen, but is shown to be carrying multiple ID cards also identifying him as Jay Garrick, Barry Allen, and Wally West. His speed during his first episode run-in with Clark makes it clearly apparent that his super-speed ability and potential surpasses Clark's completely as he is seen running backwards but able to keep Clark completely at bay as he attempts to tag Bart. Beyond that, Bart merely uses more of his power and disappears completely in plain sight of Clark, leaving him behind, bewildered but content. Their mutual respect made it apparent that they had become friends towards the end (as Superman and Flash are good friends in the future), with allusions being made to forming a "league" one day. It is mentioned that he got his powers through an accident, rather than genetics as in the actual comics, though it should be noted that at least one of the Flashes has gotten his powers through an accident. This incarnation of The Flash is also one of the few characters on Smallville who is not a 'Meteor Freak', meaning they have not acquired their powers through Kryptonite-related means via one of Smallville's infamous meteor showers.
Although commercials for "Run" billed him as "the Flash", he is never called by this name in the episode. Instead, in "Justice", he has been given the codename "Impulse". Like in the comics, Bart did not pick this name himself. In his second appearance, Bart has grown up some, but maintained roughly the same personality. However, he is now using his powers to help others. Along with Aquaman, Green Arrow, Cyborg and Black Canary he now works to stop one of Lex Luthor's evil side projects, 33.1.
Later in February 2007, director Shawn Levy was announced to be attached to The Flash and to oversee the writing of the new draft, which would use elements of Goyer's script. Ryan Reynolds expressed interest in the role once more of The Flash if the new script's incarnation was Wally West.
In October 2007, director David Dobkin said that he was signed on to direct The Flash, replacing Shawn Levy. Dobkin said that the film would work as a spin-off from the upcoming Justice League of America film. He said that the incarnation of the Flash would be Wally West. In the February 08 issue of Wizard the Flash was placed for a 2008 release date. However, this obviously fell through as well.