Watch Supergirl Season 3 Episode 21 online via TV Fanatic with over 1 options to watch the Supergirl S3E21 full episode. Affiliates with free and paid streaming include Amazon.

Episode Details

On Supergirl Season 3 Episode 21, Kara considers a major life deicsion while J"onn discovers DEO guns have hit the streets of National City.

Rating: 3.6 / 5.0 (90 Votes)
Episode Number:

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.