Oliver Queen might want to sit down, because Barry's got some bad news. In the latest promo for "Invasion!," the upcoming crossover between "Supergirl," "The Flash," "Arrow" and "DC's Legens of Tomorrow," the Flash gathers Green Arrow, Felicity and Thea to tell them about the impending alien invasion.

From there, the new trailer teases an interaction between Supergirl and Heatwave, Speedy takes charge, Vixen loses hope of survival and more. Felicity and Cisco also team up and kick down a door, while Heatwave toasts a Dominator and Citizen Steel, Spartan, Heatwave and Vixen rush an unseen threat with their guns drawn.

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Once in the “Arrow”-verse, Supergirl will join the Flash, Green Arrow, the Legends of Tomorrow and their friends in order to stop an alien invasion. With them, she’ll face down the Dominators, mind-controlling aliens who have grown so concerned about Earth’s metahuman threat that they have decided to stomp it out before it can reach the stars.

Starring Melissa Benoist as the Girl of Steel, “Supergirl” airs Mondays at 8 pm ET/PT on The CW. The network is also home to Grant Gustin as the Scarlet Speedster in “The Flash,” airing Tuesdays at 8 pm ET/PT, Stephen Amell as the Emerald Archer in “Arrow,” airing Wednesdays at 8 pm ET/PT and Arthur Darvill, Brandon Routh and Caity Lotz in “DC’s Legends of Tomorrow,” airing Thursdays at 8 pm ET/PT.