The CW has released the first full trailer for its epic mashup between Arrow, The Flash, Supergirl and Legends of Tomorrow. New footage for next week's four-part event shows the team of superheroes battling a powerful alien force known as the Dominators, and we get to see them swarm the Earth with invasion ships and lay waste to a World War II-era U.S. army. There's also a cute moment where Kara learns how Heatwave got his name.
Watch the full trailer below:
The four-hour event begins with next week's episode of Supergirl, on November 28.