Supergirl delivered another heartwarming episode in “Human for a Day.” We also got a wonderfully big reveal, the secret behind those menacing red eyes. When we last saw Supergirl, she had blown her powers battling the android, Red Tornado. Even though Kara has struggled to find her balance between Kara Danvers and Supergirl, she feels completely helpless without her powers. Kara needs radiation from Earth’s yellow sun for her powers to return, but there’s no telling how long this could take. By the time Kara gets to Catco, she has a cold. Cat immediately tells Kara to go home; Cat makes it seem like the world will end if she becomes sick from Kara.

Kara is walking the streets feeling bored and powerless. James tries to show her the bright side of having no responsibilities for a day. Then he jinxes everything by saying, “The world can survive without Supergirl for a day.” Now queue a sudden earthquake in National City. Since Supergirl doesn’t have her powers, Kara tries to do what she can as a human. Maxwell Lord is using the earthquake as a branding opportunity and as an opportunity to bash Supergirl. Kara and James try to help injured people with Lord. Kara says that the people of National City need hope, and Lord is only spreading fear.

Cat Grant also sees this earthquake as a branding opportunity, but she wants to use her voice for good. Cat takes what Supergirl stands for and turns herself into the voice of hope for National City. Cat tells the city, “Supergirl has faith in us, so let’s have a little faith in her. Supergirl will return when we need her most.”

“Human For a Day” — Kara and her friends must rely on their inner strength and courage when an earthquake strikes National City, on SUPERGIRL, Monday, Dec. 7 (8:00-9:00 PM, ET/PT) on the CBS Television Network. Pictured left to right: Luke Macfarlane and Melissa Benoist Photo: Darren Michaels/Warner Bros. Entertainment Inc. © 2015 WBEI. All rights reserved.

Moments later, Kara and James sees a man go into a convenience store with a gun. Even without her powers Kara can’t just watch. She changes into Supergirl and walks into the store. James warns her that the bullets won’t just bounce off of her, but she says that the bad guys don’t know that. Supergirl uses her kindness and everlasting hope in mankind to talk the man out of doing something wrong.

The famed Jimmy Olsen is finally seen behind the camera and takes a beautiful picture of the would be robber handing over his gun to Supergirl. Kara can’t help but be overcome with joy at the picture. James reminded Kara, “The truth of this moment is that you don’t even need powers to be a hero.”

Meanwhile, Alex is stuck at the DEO with Hank Henshaw, whom she doesn’t trust. The earthquake has caused an alien named Jemm to break loose from his prison cell. Jemm can control minds, so he is particularly difficult to contain. With Alex’s distrust of Hank, capturing Jemm turns into a disaster. Alex ends up venturing out on her own and gets into trouble in a one-on-one combat situation with Jemm. Henshaw has to come and save the day. Alex can’t take it anymore and confronts Henshaw once and for all.

“Human For a Day” — Alex’s mistrust of Hank reaches a breaking point when the earthquake traps them in the DEO with Jemm (Charles Halford), a powerful alien escapee, on SUPERGIRL, Monday, Dec. 7 (8:00-9:00 PM, ET/PT) on the CBS Television Network. Pictured left to right: Charles Halford and David Harewood Photo: Darren Michaels/Warner Bros. Entertainment Inc. © 2015 WBEI. All rights reserved.

Finally, we get Hank Henshaw’s story. At this point, we all know that Henshaw isn’t human. Alex reveals that she knows that Henshaw was the last person to see her father alive. Hank tells the story of the mission with Jeremiah Danvers. Hank and Jeremiah were searching for an alien. They found the alien, but Jeremiah realized that he wasn’t a threat. The alien was a refugee who wasn’t hurting anyone. Jeremiah tried to abort the mission, but Henshaw was obsessed. Jeremiah made the ultimate sacrifice; he died saving the alien.

Hank Henshaw died that day. The Hank Henshaw standing in front of Alex is a shape shifting alien, the same alien that Jeremiah saved. He promised to take care of Alex and Kara, and that’s what he’s been trying to do. He tells Alex that he is the sole survivor of his planet, the last sun of Mars. Then he says the words we were all waiting for, “My name is J’onn J’onzz.”

I have to admit that I have been watching Supergirl solely as a spectator. I haven’t done extra research on comic book lore about Supergirl or her allies and villains. When I read the rumors that Hank Henshaw had to be Cyborg Superman, I was disappointed, since he’s a supervillain. Much to my surprise, I was actually correct in my suspicion that Henshaw was Martian Manhunter. Now, I have to speculate that this leaves the writers open to bringing back the real Hank Henshaw as the supervillain, Cyborg Superman. For now, I’ll enjoy knowing that we can trust this Henshaw.