'The Flash' season 3 episode 8 spoilers: Aliens attack Central City as Flashpoint reveals more time aberrations?

The Flashpoint has brought more than a handful of changes to Flash's (Grant Gustin) world, but could it have brought on an alien invasion, too?

In the upcoming DC Week, the crossover event that kicks off in "Supergirl" gets a much needed elaboration on "The Flash" the following night. The alien race known as the Dominators drop in on Central City and send the Flash racing over to Star City to ask his good friend and trusted ally the Green Arrow (Stephen Amell) and his team for some assistance.

But after the Dominators prove to be stronger than any adversary that the Flash and the Green Arrow's time-tested alliance has ever faced, they work together to track down White Canary (Caity Lotz) and the rest of the Legends. They even bring their very own alien ally, Supergirl (Mellisa Benoist), over to their team.

The official trailer for the "Heroes v Aliens" crossover seems to hint that things may not work out so well among these ragtag band of heroes, especially with the addition of an alien superhero they hardly know. The Green Arrow for one, doesn't look very impressed or pleased with the perky blond girl in the red cape. Supegirl herself seems rather weary of the ragged fire-wielding Heat Wave (Domini Purcell), who just point blank tells her how he burned his family alive.

To add to the potential in-group conflict, one shocking secret related to the Flashpoint timeline is revealed, which could potentially put their fight to save the world in jeopardy. What is this secret and how does its revelation affect the heroes' dynamics? Could one of them be exposed as a traitor?

Meanwhile, Wally (Keiynan Lonsdale), who has just become a speedster, wants to jump into the fray and join the fight for humanity. Can he put aside his superhero instincts and listen to his sister Iris' (Candice Patton) advice to stay down? Or does his rebellion become a valuable asset to the team?

The "Heroes v Aliens" crossover event kicks off with "Supergirl" on Monday, Nov. 28, and carries on over to "The Flash" on Tuesday, Nov. 29, "Arrow" on Wednesday, Nov. 30, and "Legends of Tomorrow" on Thursday, Dec. 1. All shows will air at 8 p.m. EST on The CW.