Watch Supergirl Online: Season 3 Episode 21

at .

What decision did Kara make?

That was revealed on Supergirl Season 3 Episode 21 when the hero realized that a change was coming and she had to be on the good end of it. 

Meanwhile, J'onn learned that a special DEO-caliber gun was making the rounds on the streets of National City. 

This put him at odds with other members of the team who had differing opinions about how to deal with it. 

Use the video above to watch Supergirl online right here via TV Fanatic. 

Get caught up on all the latest twists and turns right now. 

Paul Dailly is the Associate Editor for TV Fanatic. Follow him on Twitter.

Show Comments
Tags: ,

Supergirl Season 3 Episode 21 Quotes

Kara: When you went away to college, we figured that out, we did that.
Alex: Yeah, I mean we called and emailed every day. What's Wi-Fi like in space?

Lena: How do you feel?
Sam: It's a cliche, but I feel like I got hit by a bus.