Previously on "The Flash," "Arrow," and "Legends of Tomorrow"...
Since we learned of them,
we've been calling them the Dominators.
You can't do this alone.
I don't plan to.
Guys, thanks for coming.
This is Kara Danvers. Supergirl.
I went back in time to change the timeline.
It's called Flashpoint,
and now things here are different
than before I left.
You just erased a daughter from my life?
He took it upon himself to change the timeline,
and, because of it, my brother was killed.
There's no amount of feeling bad
that could ever make up for that.
I'm having memories of a stranger,
but she's not really a stranger.
What if, when you interacted with your younger self in 1987,
- you-- - Inadvertently changed my past.
Oh, it's so good to see you.
I love you, Dad.
Tell her these Dominators aren't here peacefully.
Maybe they chose us because we couldn't fight back,
because none of you are Meta-humans.
What is their plan?
The phrase loosely translates to,
"We are nearing completion of the weapon."
I can't believe that you guys escaped an alien spaceship.
Key words: alien spaceship.
- I have questions. - They can wait.
Thanks for helping me get my sister home.
What's our status?
Nothing, since the Dominators
paid their little visit to mess with our heads.
Why would they do that?
What if they were trying to pit us against each other,
in order to gain intel about meta-humans?
Man, I wish they would just send us an IM with a questionnaire.
Well, Metas pose the biggest threat to their invasion.
It would make sense they'd want to get to know their enemies.
By kidnapping people.
Perhaps they were searching your minds
for potential Meta-human vulnerabilities.
I think it's time we return the favor.
What do you want to do? Kidnap one of them now?
Ever since we fought off that one ship,
they've kind of been in short supply.
Actually, I know where to find one.
I've been reviewing old army footage
of their first encounters with the Dominators,
and I think I pegged the fight to...
Redmond, Oregon. 1951.
You're suggesting we travel to 1951,
abduct a Dominator, and interrogate it
to determine their intentions.
They kidnapped us. Seems fair.
Time travel. I'm definitely in.
Okay, hold on, though.
Professor Stein and Caitlin have been talking about a way
to take down the Dominators.
They could probably use your help.
Yeah, I mean, I'm with him,
mostly 'cause I just don't want to lose my geek cred,
but time travel!
I could take Amaya and Mick.
- Do it. - Okay.
And, uh, the new president called,
which would be cool under different circumstances,
but she wants to meet with us.
Let's bring Ray and Sara as backup.
What about me? I can do backup.
Can I talk to you for a second?
I don't know.
I would like to minimize your involvement in this.
Why? Because I'm an alien?
I also happen to be your biggest weapon.
You are an unknown quantity, and this is not personal.
Except that's exactly how this feels.
Kara, when I started living this life,
it was just me.
I was going up against human threats...
that I could handle.
Then it was Meta-humans, and I can handle that.
Now I learn that there are multiple Earths,
and I was brainwashed aboard an alien spacecraft--
I am sure that was unnerving, but I don't--
I don't get unnerved.
But when I go up against something new,
I push back.
Right or wrong, it is who I am,
and it is what I do,
so I'm asking for a little bit of space
because I have to draw the line somewhere.
I need to claw back a sense of normalcy.
Please stay here.
This ship is everything!
What type of propulsion system does it use?
Oh, my God. That construct on the bow
looks like it could be some sort of time sphere.
Yeah, no idea.
To operate a ship of this size,
the deep-link nets would have to be--
Oh, my God, you'd have to use, like, a quantum neural chipset--
Hey, guys, guys.
Amaya and Rory are waiting for us on the bridge.
Can we just keep moving this along?
- This ship is... - Automatic?
- Supersonic. - Hypnotic.
It's highly unlikely we can fashion a weapon
with sufficient force to overcome the Dominators.
I was thinking the exact same thing,
which is why I invited--
So what if, instead, we try to attack them
with something infinitesimally small?
I'm--I'm sure you're familiar with the story of the lion
with the thorn in his paw.
You used to love telling me that story when I was a kid.
The lion with the thorn in his paw is a parable,