Title: The Flash (season 6)
Content:  The season premiered on October 8, 2019, in the United States on The CW. It was initially set to run for 22 episodes, but as production on the season could not continue due to the COVID-19 pandemic, the nineteenth episode was later announced as the season finale.
Title: The Flashing Blade
Content:  It was perhaps most notorious for the fact that on its last two (conventional) broadcasts, the final episode lost vision through an apparent fault with the film stock; a considerable disappointment to its viewers after it had been running for many episodes over many weeks. The final few minutes of the last episode were later shown on Michael Aspel's "request a repeat" show Ask Aspel.
Title: The Flash (season 8)
Content:  The season premiered on The CW on November 16, 2021. Two weeks before the premiere, on November 5, 2021, the CW announced their midseason schedule for their shows, announcing that after "Armageddon", The Flash will air on Wednesdays starting March 9, 2022. Prior to the season premiere, Eric Wallace confirmed that the season would only have 18 episodes.
Title: The Flash (season 7)
Content:  The seventh season premiered on March 2, 2021, delayed from its previous date of February 23, 2021. Despite premiering much later than previous seasons, it was not expected to have a much shorter episode count. In September 2020, Wallace said the number of episodes for the season had not yet been decided, and that would depend on when the season would begin filming safely. On May 25, 2021, it was confirmed that the season 7 finale would be on July 20, and that the season would have only 18 episodes, meaning that season 7 is the shortest season yet.
Title: List of Flashpoint episodes
Content: Flashpoint (TV series) 
Title: Flashpoint (TV series)
Content:  on June 17, 2011, to be simulcast by CBS. On June 1, 2011, Bell Media announced that the network ordered another season of Flashpoint, containing 18 new episodes. starting to air in Canada in September 2012. Filming of season 5 took place between February 9 and June 27, 2012. The show producers later revealed that the order had been shortened to 13 episodes. On May 1, 2012, the producers announced on their Facebook page that they had decided the fifth season would be their last. CTV confirmed the reduction in the episode order and the ending of the show on May 1.
Title: Flashback (TV series)
Content:  The half-hour series was broadcast Sundays at 7:30 p.m. (Eastern). Its debut was 23 September 1962, and its final episode was broadcast 16 June 1968.
Title: List of Flashpoint episodes
Content:  Flashpoint's fifth and final season premiered on September 23, 2012, on CTV. The series finale aired on December 13, 2012.
Title: The Flash (2014 TV series)
Content:  second. On April 2, 2018, The CW renewed the series for a fifth season, which premiered on October 9, 2018. On January 31, 2019, The CW renewed the series for a sixth season, which premiered on October 8, 2019. On January 7, 2020, the series was renewed for a seventh season, which premiered on March 2, 2021. In April 2020, Gustin, who had been contracted for seven seasons, said there had been discussions about renewing the series for eighth and ninth seasons, but those were stalled due to the COVID-19 pandemic. On February 3, 2021, the series was renewed for an eighth season which premiered on November 16, 2021.
Title: The Flash (season 5)
Content:  The season premiered on The CW in the United States on October 9, 2018. The annual crossover episode swapped time-slots with Supergirl for that week and aired on Sunday, December 9.

Question: when was the last episode of the flash aired?
Answer: May 22, 2018.
May 1, 2018.