Supergirl has done a great job at tackling some difficult subjects while not hitting us over the head with it. “Changing†is by far one of their most important episodes to date. Alex is having a tough time with some personal realizations. Kara and Mon-El go head to head, and a scare brings M’gann and J’onn closer together.
Some scientists in Norway found a wolf who supposedly died thousands of years ago but somehow still felt warm. There was a parasite inside the wolf, and the scientists of course let it out. Dr. Jones got the parasite infecting him, and he’s frustrated that humans are destroying the Earth. Dr. Jones knows that the parasite is inside of him, and he seems to like the power that comes with it. The parasite can suck up power from people, and Supergirl gives him a taste of real power.
The parasite sucks up so much power that Dr. Jones has officially become an unrecognizable monster. Supergirl and J’onn go to take on the monster, but they both fall susceptible to the parasite’s powers. Back at the DEO, Kara and J’onn are unconscious and are not getting better anytime soon. Now who is going to step up to the plate?

Kara has been working with Mon-El to teach him to be a superhero. What she failed to do was figure out what Mon-El actually wanted to do on Earth. Mon-El reminds her that just because he doesn’t want to fly into danger doesn’t make him a bad person. Kara wants so badly for him to be just like her that she hasn’t given him enough of a chance to find himself here on Earth. But, when Kara is in trouble, Mon-El finds a way to step up. Alex is frustrated that Mon-El is acting like a coward, but he worries that he won’t know what to do to be a hero.
Well, he learns to step up because when Supergirl and J’onn are down, Mon-El shows up to fight the monster. And, he’s not the only one. James Olsen gets to reveal himself as The Guardian once Winn has finished the design for his suit. The suit works pretty well, but thankfully, Supergirl is able to come and save the day. She realizes that she can overload the monster with Plutonium 239; no one can absorb that much power. The monster is defeated, and Supergirl is curious about the help she got from The Guardian. When she uses her x-ray vision on him, she can’t see through the suit. Winn made it out of lead. For now, he will remain a mystery, but I’m not sure how long they can keep this secret from Kara.
Alex has had one of the most beautiful transformations on this show. We saw her when she was just a DEO agent taking orders and always coming second to her superstar of a sister. Now, Alex has gotten to enjoy some time in the spotlight. After realizing last week that she has feelings for Maggie, she goes to confront Maggie. Maggie gives her the perfect advice; Alex needs to come out to her family. Alex is of course confused and terrified; she worries that maybe this isn’t even real. But, in her heart, she knows that Maggie right; she needs to come out to her family.

Alex talks with Kara and understandably has difficulty spitting the words out. Once Kara realizes what she’s trying to say, she asks a bunch of questions. Kara is trying to be supportive, but it seems that Alex wasn’t ready to answer questions. Kara actually questions if Alex is sure this is what she wants. I doubt Kara meant it the way that Alex took it, but Alex eventually explained that she thinks she always knew. She had a best friend in high school who she had feelings for, but she just suppressed the feelings because they terrified her.
Later, Kara encourages Alex to tell Maggie how she feels. Alex is worried that Kara is disappointed in her, but Kara would never feel that way. Kara remembers that while they were kids, everything was pretty much always about her and her secret. She’s glad that Alex feels comfortable enough to share with her now and feels bad that Alex wasn’t able to share when they were kids. I appreciate that even though it’s not the same, Kara knows how it feels to keep a part of yourself shut off, and she reminds Alex that she doesn’t have to go through this alone. Unfortunately, Maggie doesn’t want to pursue a relationship with Alex; they are just in different points in their experiences. Alex is crushed, but hopefully she can feel more comfortable in herself moving forward.