where did the filming take place ?
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what episode of arrow does the flash start . The event began on December 2, 2014, with "The Flash" episode "Flash vs. Arrow" and concluded the next day with the "Arrow" episode "The Brave and The Bold". what is the episodes  plot ? The crossover sees Team Flash helping Team Arrow take on the boomerang-wielding villain Captain Boomerang. when was it released ? The event began on December 2, 2014. what were its ratings ? It had the highest 18-49 rating since the second episode.
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Flash vs. Arrow [SEP] Ratings
"The Flash" episode had the second-highest number of viewers following the series premiere on October 7, 2014, and the highest 18-49 rating since the second episode. Viewership rose 22% and the 18-49 rating by 14%, over the previous episode, "Power Outage". The "Arrow" episode was the most viewed of season three, and had the show's largest audience since the series' premiere on October 10, 2012, and a series high 18–49 rating. Its viewership grew by 46% and its 18-49 rating by 56% over the previous episode, "Draw Back Your Bow", and helped contribute to the most watched Wednesday on The CW in more than two years.