By Nick Romano
March 19, 2017 at 06:07 PM EDT
The CW

“Since we’re fighting aliens, I figured we get one of our own.” 

The CW’s four-night crossover event kicks off with Supergirl this Monday, in which The Flash speeds into Kara’s Earth to enlist the Kryptonian strongwoman in the fight against The Dominators, an alien race invading Earth. A new trailer welcomes her to “the best team-up ever,” and shows off new footage of the enemy invaders as they face Team Arrow and the Legends of Tomorrow

As the extended preview showed, The Dominators have descended upon Earth in the hopes of destroying the meta-humans before they can be weaponized against their race. In this new look, Barry Allen (Grant Gustin) compares them to “World War Z zombies,” as in “no military can stop them.” 

But they aren’t the only threat: Deathstroke makes an appearance, but he’ll have to contend with White Canary (Caity Lotz) before he can drive his sword into anybody. We also catch glimpses of Heat Wave and Vixen in what appears to be an alternate timeline battle (if you compare the 0:43 mark of the trailer to this promo clip), Oliver Queen’s (Stephen Amell) new crossbow, and other characters like Wild Dog and Citizen Steel. 

Supergirl airs at 8 p.m. on Monday on The CW. The crossover continues with The Flash (Tuesday at 8 p.m.), Arrow (Wednesday at 8 p.m.), concluding with Legends of Tomorrow (Thursday at 8 p.m.).

Watch the trailer above, and see photos and more footage from the crossover.