'Captain Boomerang' Debuts In ARROW Season 3, Episode 8; "The Brave and the Bold"
So, we know what to expect from the first part of the Arrow/The Flash crossover, but how about the second? Well, the action heads back to Starling City and the villainous Digger Harkness, a.k.a. Boomerang takes center stage as The Arrow enlists the help of the Scarlet Speedster...
PART TWO OF THE ARROW AND FLASH CROSSOVER EVENT — Oliver (Stephen Amell),Arsenal (Colton Haynes) and Diggle (David Ramsey) track down the location of a boomerang-wielding killer named Digger Harkness (guest star) but are surprised when they come face to face with an A.R.G.U.S. team. Diggle asks Lyla (guest star) why A.R.G.U.S. is involved but she defers until Harkness attacks the building, killing several agents and targeting Lyla. The Arrow joins the fight and gets help from an old friend – The Flash (guest star Grant Gustin). Harkness manages toget away and Oliver teams up with Barry again to find him before he can get to Lyla. When Harkness plants five bombs in the city that are timed to explode at the same time, both teams must come together to save the city. Jesse Warn directed the episode with story by Greg Berlanti &Andrew Kreisberg, and teleplay by Marc Guggenheim & Grainne Godfree Schwartz (#308).
So, there's not quite as much information in here as the description for "Flash vs. Arrow" (which you can read by clicking here), but it sounds like Captain Boomerang will play a HUGE role in this episode. Seeing The Flash in the more grounded world of Starling City should be very interesting, even if the two parts of the crossover sound a little more self contained than expected...