This comes as a surprise to virtually no one, especially since the "backdoor pilot" built into Arrow's second season was cancelled in order to make way for it. After all, if the answer were going to be no, that would have been a great boon for Arrow, to have a high-profile DC Universe episode in its back nine.
The pilot will also star Law & Order veteran Jesse L. Martin as Detective West, Barry Allen's surrogate father and the biological father to Iris West (who eventually married Barry in the comics). The Vampire Diaries‘ Rick Gosnett and Danielle Panabaker of Piranha 3DD fame have been cast as probable villains Eddie Thawne (the Reverse-Flash) and Caitlin Snow (Killer Frost).
Arrow's Andrew Kreisberg and Greg Berlanti will executive produce. The pilot episode is also rumored to involve the young DC Comics hero known as Vibe.