when did the flash first appear on arrow
second season
title: The Flash (season 1) text: The Flash (season 1) 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. The series follows Allen, portrayed by Grant Gustin, a crime scene investigator who title: Flash vs. Arrow text: Amell, Gustin, David Ramsey, Emily Bett Rickards, Danielle Panabaker and Carlos Valdes were joined by executive producers Berlanti, Kreisberg and Guggenheim for a Q&A panel. The first part of the crossover, "The Flash", was broadcast on December 2, 2014, followed by part two on "Arrow" on December 3, both on The CW. The crossover was simulcast with the US broadcast in Canada on CTV. It first aired in the United Kingdom on Channel 5 on December 16 and December 18, 2014. In Australia, the episodes aired back-to-back on January 28, 2015, on Fox8, after Nine Network, which broadcasts "Arrow", allowed title: Arrow (TV series) text: of soundtracks was also released. In October 2014, a spin-off series entitled "The Flash" premiered. In August 2015, an animated spin-off, "Vixen", was released, while a second live-action spin-off, "Legends of Tomorrow", premiered in January 2016, featuring several characters from "Arrow" and "The Flash". All four shows are set in a shared universe collectively known as the Arrowverse. On April 2, 2018, The CW renewed the series for a seventh season, which premiered on October 15, 2018. The series follows Oliver Queen, billionaire playboy of Starling City, who is discovered on the mysterious island of Lian Yu five years after title: The Flash (season 4) text: from Earth-X. "Arrow" actor David Ramsey appears as John Diggle, as well as DeVoe's Diggle disguise earlier in the twenty-second episode. The season began airing on October 10, 2017, on The CW in the United States, and on CTV in Canada. The season concluded on May 22, 2018. Sky One acquired the rights to air the season in the UK & Ireland, airing it alongside the other Arrowverse shows. The season premiered October 17. In July 2017, cast from the series appeared at San Diego Comic-Con International to promote the season, where exclusive footage was shown. During the panel, a title: Green Arrow text: initially a well-known character outside of comic book fandom: he had appeared in a single episode of the animated series "Super Friends" in 1973. In the 2000s, the character appeared in a number of DC television properties, including the animated series "Justice League Unlimited", "Young Justice", "The Batman" and "", and several DC Universe Animated Original Movies. In live action, he appeared in the series "Smallville", played by actor Justin Hartley, and became a core cast member. In 2012, the live action series "Arrow" debuted on The CW, in which the title character is portrayed by Stephen Amell, and launching