With this year's Arrowverse crossover, "Elseworlds," exactly one week away, The CW has released a trailer providing an extensive look at the epic DCTV event.

The extended clip shows Stephen Amell's Oliver Queen waking up under Barry Allen's identity as The Flash with Iris West-Allen unaware of the changes to reality. As the hero regroups with Barry, under his identity as the Green Arrow, and Supergirl, they find a threat that endangers of all the DCTV Multiverse.

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"Enough! You will not do to this Earth what you did to mine!" declares John Wesley Shipp as the 90s Flash.

While the heroes are briefly seen gathered around the Bat Signal and another glimpse of Batwoman in action is seen, the villains, including evidently The Monitor, have a hard-hitting enforcer of their own in a black-suited incarnation of Tyler Hoechlin's Superman.

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This year's Arrowverse crossover event will involve the casts of Supergirl, Arrow, and The Flash. The event will unfold over three nights, starting with a special episode of The Flash on Sunday December 9 at 8 p.m. ET/PT. Then, it continues Monday, December 10, with Arrow and concludes on Tuesday, December 11, with Supergirl.