When Arrow moves to Russia for its Season 5 flashbacks, it will make last year’s magical island adventures look like a picnic by comparison.

In exploring Oliver’s history with the infamous Bratva crime syndicate, “We really wanted to go gritty, dark, and make it feel very real,” showrunner Wendy Mericle tells TVLine.

“We’re dealing with the Bratva, and the Bratva is, as we all know, a pretty interesting and messed-up institution. I might get shot for saying that, but hey!” she adds with a laugh.

In order to make sure that the upcoming episodes stay true to that unflinching world, the creative team did their research. “Everyone on staff watched [the 2007 film] Eastern Promises,” Mericle says. “I watched documentaries about Bratva and how they operate in Russian prisons.”

But it’s not just crime bosses Oliver has to fear as he tries to keep his promise to ill-fated island pal Taiana, to tell her parents what happened to her and brother Vlad. A new Big Bad, played by Rocky IV opponent Dolph Lundgren, also awaits him in the flashbacks.

“[Dolph’s character] is a government strongman,” Mericle previews. “He is scary and formidable — and he had a role in some stuff with Taiana’s family last season. He’s a bit of a badass.” Ya think?

Arrow returns Wednesday, Oct. 5 at 8/7c on The CW, where it now leads into the freshman drama Frequency.

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