Both Arrow and The Flash have sustained plenty of crossover in their first seasons occupying the same cinematic universe, but with either finale only weeks away, worlds in crisis will undoubtedly collide. Now, we know for certain that Barry Allen will race over to Arrow once more for the Season 3 finale, putting some flash in “My Name is Oliver Queen.”

Entertainment Weekly broke news of the latest crossover, confirming that Grant Gustin’s Barry Allen will appear in May 13 Arrow finale “My Name is Oliver Queen,” just days before The Flash’s own season finale “Fast Enough” on May 19. Granted, We already knew that Oliver will appear on The Flash’s May 12 installment “Rogue Air,” seemingly freed of the League’s mind-control, and … okay, now I’ve gone cross-eyed.

Additionally, executive producer Marc Guggenheim had some ominous words for the hour:

We’re at the point in the season where, I think our fans know, it’s usually when the culling happens, so I think everyone knows that they’ve got reason to be afraid. The season 3 finale of Arrow is very definitive. It really feels like the end, not just of season 3, but of the first three seasons.

Bewaring potential spoilers, so reads the Arrow Season 3 finale description for “My Name is Oliver Queen”:

THE HEART-STOPPING SEASON FINALE — Everyone’s lives are in danger as Ra’s al Ghul (guest star Matt Nable) puts forth his final plan. Oliver/Al Sah-him (Stephen Amell) must decide if he’s strong enough to take on this new role and what it will mean for everyone on Team Arrow, and his soul.

Guggenheim also noted that while the season won’t end on a traditional cliffhanger, we might not expect direct setup for the Legends of Tomorrow spinoff either. In the meantime, Arrow will air its penultimate Season 3 installment “This Is Your Sword” later on tonight. Will Barry and Oliver’s next crossover be the biggest yet?

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