Barry asks Green Arrow for help when aliens attack Central City, but when they realize that won’t be enough, they track down the Legends of Tomorrow so they can bring Supergirl in on the battle.

The Flash really kicks off the 4 night crossover between Supergirl, Arrow, DC’s Legends of Tomorrow, and The Flash. While it technically started on Supergirl, that episode really didn’t deal with much of the greater story. This is the real beginning.

The episode is broken down into two parts, the gathering of all of the heroes and the first battle with the alien invaders.

That first part, where everyone is gathered, is absolutely fantastic. Watching the various personalities come together is so much fun. Sueprgirl’s perky/bubbly personality with Oliver’s grumpiness is the perfect oil and water situation and then there’s Heatwave, and more to contend with. It really feels like all of the actors are having a lot of fun with it all. It comes across on the screen and that makes the episode a lot of fun. That melding of so many just creates an energy all of the shows on their end don’t quite reach and some really lack.

The episode is also really smart in its use of Kara/Supergirl. Through her viewers are introduced to all of the other characters, their names and personalities. It’s an interesting way to go about it all and very intelligent writing. There’s a chance that there’s not crossover between viewers so to catch folks up is a good thing to do.

The second half of the story is the initial attack by the heroes. That’s somewhat paint by numbers with some being turned and their battling each other. It’s entertaining and interesting in seeing who steps up and how and how the different characters’ powers interact. It’s good, but feels like a typical comic story.

But, what’s really interesting is the episode diving into the fact that Barry has changed the timeline. This is his first chance to dish to Team Arrow and things really blow up as far as that. There’s also some teasing about Barry in the future and what’s to come. Throwing that in the episode will hopefully intrigue new viewers, but also get long time viewers excited. It’s a fantastic balance of focusing on the crossover, but setting up the future too (no pun intended).

Overall, a solid episode that really gets things running and I can’t wait to see what else is still to come.

Overall Rating: 8.85