Kara has longed to feel normal. Well, now she gets her chance. The fight with Red Tornado last week drained her powers, leaving her vulnerable to everything that plagues us mortals. For instance? Colds! Supergirl? More like Snifflegirl. Cat is none too pleased that her assistant is the one sneezing in the office. “You never get sick, that’s the best part about you,” she says. She shames Kara into leaving. Unfortunately, it looks like Supergirl may be needed. The DEO has a nasty psychic alien named Jemm in containment. “I will grind your love ones to dust,” the alien says. Hank replies: “There are none left to grind.” Now that's a curious admission. On the street, away from germaphobe Cat, Kara runs into James. He tells her to "enjoy [her] time off." Too bad an earthquake hits. Kara tries to face down a car, but James pushes her to safety, inadvertently breaking her arm. (He gives her his shirt to serve as a sling. Hello, James Olsen's muscles.) In the commotion Jemm gets loose, and the DEO goes under lockdown. The Alura hologram tells the DEO staff that Kara is the only hope they have at stopping Jemm. Well, we know that's not an option, so Hank organizes a team to pursue the alien. The DEO agents will wear neural disruptors so Jemm's psychic powers can blocked. Hank does not let the already suspicious Alex come along. Winn gets the TVs working at CatCo again, which means that everyone can listen to Maxwell Lord complaining that Supergirl isn’t around. Cat enlists Winn to help her run opposition on Maxwell. (She was apparently unaware Winn existed until this moment.) James and Kara go check out Maxwell’s relief efforts. Maxwell suspects what is actually true: that Supergirl’s powers are at least temporarily gone. A woman runs to them in a state of panic when her dad is hurt. Supergirl could have easily saved his life, but Supergirl's not around. Kara is pained when she realizes she can’t do anything. Jemm kills the agents that accompanied Hank, and Hank vanishes, but not for long. He reappears, and plans set out again. He says that there is only one disruptor left, and again leaves Alex behind. Hank tells Alex to trust him, but that's not happening. Alex sees similarities in this case to the one involving her father, so she enlists her colleague Donovan to defy Hank's orders. Kara is dejected. “These past few weeks have been the best of my life,” she says. She was able to do good. Now she's feeling "helpless." James tells her: “What you’re feeling is human." He says her that no one can save everyone, but a true hero continues to try. Kara takes this at face value, when she sees people breaking into a store. Back at the DEO, Alex realizes she was right. Hank was lying. The fallen agents' distruptors were not destroyed. Donovan doesn’t put one fast enough, and is ensared by Jemm. He points his gun at Alex. (For Jessica Jones viewers, Jemm's powers may come off a little Kilgrave-y.) Kara is also staring down a gun's barrel. Dressed as Supergirl, she starts talking a robber down just as Cat broadcasts about how Supergirl’s “spirit” is still with the residents of National City. “Supergirl will return when we need her most,” Cat says. The man hands over the gun to Supergirl, and James snaps a photo. Kara may have temporarily triumphed, but Alex is still in a precarious situation. She’s ambushed by Hank, but Alex turns her gun on her boss and decides it's time to air her grievances, telling him what she knows about her father. She tells Hank to cuff himself to nearby bars, and offers herself up to Jemm. Kara is exhilarated by her success, and by James' photo. She asks James about the first photo he ever took, and he opens up about his father, who gave him a camera and died in the Gulf War. He then returns to the photo of Kara. “The truth of this moment is that you don’t even need powers to be a hero,” James tells her. They hug, sweetly. While they are embracing, Winn walks in with information on how Kara might get her powers back. He stumbles over his words, explaining that she basically needs "Kryptonian version of extreme adrenaline." Kara tries to console the heartbroken Winn, but he's is pissed and vicious. “The superhero never gets the guy,” he tells her. Something shakes CatCo during their conversation, but it wasn't an aftershock. It was an explosion. Winn surmises it was the gas line. Meanwhile, Alex is keeping Jemm pretty busy, attacking him with a large arsenal. It doesn’t work, but Hank drops in and starts beating the crap out of Jemm. “I told you, Alex,” he says. "I’m not the enemy." So what’s happening back at CatCo? James starts climbing the elevator shaft to help a group of trapped people. He gets them out, but then there's another jolt and he loses his grip. He’s left hanging onto a wire, which is about to snap. Luckily adrenaline kicks in and Kara's back to her full Kryptonian strength just in time to rescue him. Then she starts zooming around the city, saving a bus of children, putting out fires, and pissing Maxwell Lord off. Alex calls Kara to let her know that they are alright at the DEO, and then goes to Hank to hear his confession. He tells Alex not to share the information with her sister. “I am not Hank Henshaw,” he says. “He died the same night as your father.” Hank and her father had been following an innocent alien on Earth. Though it was peaceful, the DEO wanted to kill it. Jeremiah Danvers objected, but Hank was “obsessed.” So Jeremiah “made the ultimate sacrifice,” and died saving the alien. So where is the alien now? Right in front of Alex. He's a shapeshifter, so he took on Hank's identity, and vowed to protect Alex for her father. “I am the sole survivor of my planet, the last son of Mars,” he declares, and transforms. He is J’onn J’onzz, a.k.a. Martian Manhunter. Back at CatCo Kara tries to make amends with Winn, but he's having none of it. Winn's aggression is seriously off-putting. Sure, Kara has a crush on James, who has a girlfriend, but Winn is basically slut-shaming her for hugging a male friend. After he leaves in a huff, Kara looks into Cat’s office and gets an idea. She appears to Cat as Supergirl, and thanks her for her broadcast. “You gave them hope today,” Kara tells her. “I know that you inspired them, because you inspired me.” Kara flies away happy, but her momentary bliss is interrupted. Astra is back to stir up some more trouble just as the episode comes to a close. Uh oh. Looks like our big bad is back.