ByMichael Patterson, writer at Creators.co
I Write. Sometimes.
Michael Patterson

*Updated 12/02/2016*

The CW's annual superhero crossover is officially upon us, and this time it was bigger than ever. This year #Arrow and #TheFlash were joined by spin-off show #LegendsOfTomorrow and network newbie #Supergirl as they teamed up to take on one of the greatest evils the Arrow-verse has ever known.

So, just in case you have no idea what happened during the crossover, we're here to catch you up on everything we know about the major #TV event so far, including news, air dates, rumors, images and the brand new trailer, featuring the biggest superhero team up in TV history!

Crossover News, Rumors & Spoilers

New details of the crossover have come to light and along with them, new images have been released — which somehow make it seem so much more real. We finally have photographic proof that Supergirl is coming to the Arrow-verse! No matter what happens, there is nothing more iconic than seeing this amazing line-up of superheroes taking center stage together. These aliens have there work cut out for them!

Iconic lineup: The Green Arrow, Supergirl and the Legends together. (via EW)
Iconic lineup: The Green Arrow, Supergirl and the Legends together. (via EW)

As it was recently revealed that the Dominators possess mind-control capabilities, it appears that the returning Arrow characters, including Laurel, Moira, Robert and Deathstroke might be a part of an alien-induced dream. That could be wrong, but with Laurel appearing to be in what looks like a wedding dress, it may be a figment of Sara's imagination. We'll have to wait and see! It's just awesome to see Laurel back!

Black Canary is back: Laurel and Sara together in the crossover. (via EW)
Black Canary is back: Laurel and Sara together in the crossover. (via EW)

It has also been revealed that much like in the comics, the Dominators come to Earth as they feel threatened by the increasing number of metahumans. Furthermore, somebody will get shot during the crossover, but the question is — who?

When Will The Crossover Air?

The crossover began with Supergirl which aired on The CW on Monday, November 28, 2016. That was followed by The Flash on Tuesday 29th, Arrow on the 30th and concluded with Legends Of Tomorrow on December 1, 2016.

Promos, Posters & Trailers For The Crossover

*Updated 12/02/2016*

All installments of the CW's amazing crossover have aired, marking the end of this year's annual event. But if you're not quite that caught up yet, The CW have gifted us with plenty of trailers for the Invasion! Crossover and they're everything we could have hoped for and so much more! So, if you haven't yet watched the Crossover, here are the promos for each installment.

This full-length trailer pretty much heightened the anticipation for the crossover by revealing the one thing we all wanted to see — Supergirl's arrival to the Arrow-verse! Furthermore, it revealed the Dominators's global invasion.

While the crossover technically began at the end of the Supergirl episode, here's the promo for The Flash which acted as the first part of the Invasion! story:

And if you've already seen that installment and instead waiting for the next part, then you'll be ready to move on to Arrow. The series also celebrated its 100th episode during the crossover, so it made some time in all the madness to pay tribute to some of the things that made it a success.

Check out the promo for Arrow's "Invasion!" installment:

And if you've already celebrated Arrow's monumental achievement and just can't wait to see the next part of "Invasion!" then you'll be looking for the Legends Of Tomorrow promo, am I right?

The arc reached its epic conclusion on Legends Of Tomorrow's installment, which saw the greatest superhero team-up on TV come to an end. Check out the promo below:

And if that wasn't enough excitement for you, be sure to check out these four brand new individual crossover posters for each show. And while they are all equally amazing, the most intriguing thing about them is that when they are put together, they seem to feature the Hall Of Justice.

Hall Of Justice: The four-way 'Arrow'-verse crossover posters. (via The CW)
Hall Of Justice: The four-way 'Arrow'-verse crossover posters. (via The CW)

The Hall Of Justice is one of the most iconic DC Comics locations and is considered one of the primary Justice League headquarters. So did the arrival of the Dominators officially form a DC TV Justice League?

I f you really want to get a closeup look at the crossover, check out this exclusive Behind The Scenes video which features an interview with Supergirl herself, Melissa Benoist:

Check back here for updates!

The Dominators Are Coming

Over the years, we have seen some major big bads in the Arrow-verse. From Vandal Savage to Eobard Thawne, these guys have been downright deadly and almost unstoppable. But what threat could be major that it would make a vigilante archer, a heroic speedster, a group of time-traveling and an invincible Kryptonian team up? Well ladies and gentlemen, allow me to introduce you to the Dominators.

The Dominators are a group of intellectually advanced aliens who, in the comics, are obsessed with harnessing the power of the metagene — a gene in the human species which activates during times of physical stress, giving the person superpowers — to advance their own species, creating an alien race of metahuman aliens.

They are renowned for their role in the iconic Invasion! arc in the comics which saw them lead the Alien Alliance and taking on the Legion of Superheroes, Justice League International and Omega Men who all came together for the event. It sounds like these aliens have a knack for uniting superheroes!

How Will Supergirl Join The Arrow-verse?

As we saw last season during Supergirl's crossover with The Flash, the Girl Of Steel's show doesn't take place in the Arrow-verse. And as we recently found out, that's not going to change. But that begs the question — how will she make it to the Arrow-verse for the crossover?

Arrow and Legends Of Tomorrow Executive Producer recently revealed this, commenting that while the Monday 28th November episode of Supergirl will not be directly involved in the crossover from a storyline standpoint, the episode will end with The Flash opening a breach to her world and taking her back with him.

"Once the heroes realize that they’re up against aliens, they decide that they need an alien on their side and, fortunately, Barry knows a really nice one. I don’t think it’s a big shock that, between Barry and Cisco, and all of their experiences with Earth-2 and the multi-verse, that they can pluck her from Earth-CBS."

Thus, the official storyline will begin in the Tuesday 29th November episode of The Flash, which will see Supergirl arriving in the Arrow-verse to team up with the Flash, the Green Arrow and the Legends to take down the major threat of the Dominators.

See also:

Arrow's Offering Will Also Be Its 100th Episode

Arrow's 100th Episode will bring back familiar faces.
Arrow's 100th Episode will bring back familiar faces.

If evil aliens, Supergirl and a superhero team up wasn't enough, it turns out that Arrow's offering in the crossover also happens to be its 100th episode. So not only will we see a horde of awesome #superheroes, we have also been promised the returns of some of Arrow's most beloved faces, including Katie Cassidy as Laurel Lance, Susanna Thompson as Moira Queen and Jamey Sheridan as Robert Queen, as well as an uncredited appearance from Deathstroke.

However, it will be interesting to see how these characters will play into the crossover. Guggenheim has promised that no Flashpoint and no flashbacks will be featured during the return of these beloved characters. So, how will they return?

Katie Cassidy may have portrayed the Black Canary on Arrow for four years, but she also portrayed Laurel's evil Earth-2 doppelganger Black Siren on The Flash. And thanks to a photo Cassidy posted on twitter, we know that Black Siren will show up and it will presumably be in the crossover.

But even though she may be may be evil, Black Siren is a metahuman and that makes her a target for the Dominators. Could we see Black Siren following in the footsteps of her heroic doppelganger and help the heroes take down the aliens?

With all that's going on during the crossover, Guggenheim has promised that it won't take away from Arrow's milestone, commenting:

"In a very positive way, people didn’t want to feel like the cross-over was hijacking what should be a really seminal episode and moment for Arrow, which is wonderful. I don’t want to spoil it, but Greg came up with an idea that really does allow us to have our cake and eat it, too. It is a love letter to the show. It draws on all previous 99 episodes"

No matter how awesome the crossover is, the fact that it will be Arrow's 100th episode makes it all the more fun!

Superhugs: Barry and Kara will be reunited!
Superhugs: Barry and Kara will be reunited!

So now you can consider yourself caught up on the CW's impending major superhero crossover. With freaking aliens making their debut in the Arrow-verse, it seems like Barry Allen is going to call up his bestie from another Earth Kara Zor-El AKA Supergirl. With the Girl of Steel joining forces with the Scarlet Speedster, the Emerald Archer and the time-traveling Legends, those Dominators won't know what hit them. And if you weren't excited enough, take the opportunity to celebrate Arrow's 100th episode as well.

What is quite possibly the biggest TV Crossover of all time is almost upon us and I can't wait!

Who's there: The Green Arrow and The Flash hiding from....Diggle? (via EW)
Who's there: The Green Arrow and The Flash hiding from....Diggle? (via EW)

Are you excited for the CW's superhero crossover? Let us know in the comments below!

[Source: Collider, Katie Cassidy's official Twitter, Entertainment Weekly]