The CW is promoting the upcoming “Arrow” spin-off in the season finale preview of the superhero series. We will get to see a glimpse at Barry Allen a.k.a The Flash as he bolts across a field at lightning speeds. By the look of things, he is sporting his suit and mask! The season 2 finale of “Arrow” will give fans an extended look at the spin-off series, which is set to air Wednesday, May 14 on The CW. Titled “Unthinkable”, the season 2 finale will feature an epic showdown involving the Blood Cult and Oliver’s group of warriors.