Next month The CW will showcase its annual DC crossover, although this year the heroes of The Flash, Arrow and DC’s Legends of Tomorrow will be joined by the network’s newest superhero in Melissa Benoist’s Supergirl.
During a press event earlier this week, executive producer Marc Guggenheim offered up a few details on the crossover, which will actually begin at the end of an episode of Supergirl as Kara is enlisted by Barry (Grant Gustin) and Cisco (Carlos Valdes) to help battle the threat of the extraterrestrial Dominators.
“Some people call it a four-way crossover because it involves four shows; my ulcer requires me to call it a three-part crossover,” states Guggenheim explains. “The story that’s being told has a beginning, middle, and end: a beginning in Flash, a middle in Arrow, and an end in Legends. But Supergirl is very much a part of the whole thing, so we are crossing over four shows — four shows in three parts.”
“Last year, Supergirl established that Flash was able to make his way to what I call Earth-CBS, and it stands to reason that, with the proper breach technology, the reverse can happen,” he continued. “Once the heroes realize that they’re up against aliens, they decide that they need an alien on their side. Fortunately, Barry knows a really nice one. I don’t think it’s a big shock that between Barry and Cisco, and all their experiences with Earth-2 and the multi-verse, that they can pluck her from Earth-CBS.”
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The crossover will also take in the 100th episode of Arrow, and Guggenheim revealed that it will see the return of former cast members Jamey Sheridan (Robert Queen), Katie Cassidy (Laurel Lance), Susanna Thompson (Moira Queen), John Barrowman (Malcolm Merlyn) and Neal McDonough (Damien Darhk) as the show celebrates the landmark.
“It is a love letter to the show, it draws on all previous 99 episodes pretty much. Everyone who we could have in the episode, from a scheduling point of view, is in the episode. Even the people who we couldn’t have, because of conflicting schedules, are represented. At the same time, you’ve got Flash and Supergirl; that’s an enormous amount of fun. Certainly the recruits also play a very large role, an important role, in the episode. I’m really excited about it.”
Via EW