Popsugar Entertainment Cw Arrow The Flash Supergirl 2018 Crossover on The CW Photos This Year's Arrowverse Crossover Might Be the Most Epic One Yet — See the Photos! 16 October 2018 by Brea Cubit Image Source: Everett Collection It seems like every DC superhero crossover event on the CW gets bigger and bigger every year. We first saw Barry Allen (Grant Gustin) and Oliver Queen (Stephen Amell) join forces four years ago and the power-packed crossover expanded last year to include The Flash, Arrow, DC's Legends of Tomorrow, and Supergirl. This year, fans can expect to see an exciting mash-up of new heroic faces when Batwoman (Ruby Rose) and Superman (Tyler Hoechlin) also get in on the action. The crossover, titled Elseworlds, will take place over the span of three days, from Dec. 9 to Dec. 10. The storyline will follow Barry, Oliver, and Supergirl to Gotham City where they will team up with Batwoman to stop a crazed Arkham Asylum doctor. Judging by the latest promo poster for the event, Oliver becomes the Flash and Barry becomes the Green Arrow — um, what?! Although it sounds like a dark, twisted premise, the cast has been posting some light-hearted pictures of each other from the set, including one that confirms Hoechlin will wear Superman's black suit from the comics. Check out some of the behind-the-scenes photos and posters of your favourite Arrowverse heroes below! View this post on Instagram Suit still fits. A post shared by Stephen Amell (@stephenamell) on Oct 15, 2018 at 9:33pm PDT 1 / 5 Image Source: The CW 2 / 5 Image Source: The CW 3 / 5 View this post on Instagram Barry and Oliver have really gone next level friendship wise. A post shared by Stephen Amell (@stephenamell) on Oct 15, 2018 at 7:12pm PDT 4 / 5 View this post on Instagram Back in Black! Here we go again... @stephenamell @grantgust #supergirl #arrow #theflash #superman A post shared by Tyler Hoechlin (@tylerhoechlin) on Oct 15, 2018 at 11:57am PDT 5 / 5 CWSupergirlThe FlashArrowTV