CW's "The Flash" Promo (in "The Arrow")

CW's upcoming television series "The Flash" receives a few seconds of promo at the end of the video promo for "ARROW"s season finale (thanks SHH) posted above … and as well I found the episode (Season 2 Ep 9 of "Arrow") where "Barry Allen" - played by actor Grant Gustin - breaks out in a song like he does in "Glee" gets juiced up by a freak lightning (ala the comicbooks) which eventually turns him into everyone's favorite "Scarlet Speedster" (Check out how he looks like HERE / Tagged):