Spoiler warning: Do not read on unless you’ve seen CBS’ “Supergirl” episode 7, titled “Human for a Day.”

When we last saw Kara at the end of episode 106, she was left bleeding, with her superpowers (at least temporarily) gone. This week, her human capabilities are pushed to the limit, and Alex has her most badass moment yet in a standoff with Hank Henshaw, who finally reveals his secret identity and tells Alex the truth about her father’s death.

The episode opens with a distinctly darker tone than usual, as Kara learns how to cope with being powerless. She’s sick with a cold, which repulses Cat Grant (“You never get sick. That’s the best part about you!”), and when an earthquake strikes, Kara injures her arm. It’s difficult watching Kara get hurt, but it does provide a great opportunity for James to take off his shirt to support her injury (calm down — he’s still wearing a tank top, this is a family show).

At the DEO we learn that the earthquake that hurt Kara is a result of an alien escapee, Jemm, who intends to use his mind control abilities to release the captured aliens in the DEO’s possession. The villain’s plotline takes a backseat in this episode, but does fuel an important confrontation between Alex and Hank Henshaw.

She holds her boss at gunpoint, accuses him of killing her father and makes him handcuff himself while she takes care of Jemm. Later, when Alex lures Jemm in for the kill, Henshaw comes to her rescue and finishes off the villain. In a dramatic reveal, we learn that Henshaw is actually an alien shape-shifter (J’onn J’onzz, also known as Martian Manhunter in DC Comics canon) who was merely taking on Henshaw’s form. Alex’s father and the real Henshaw were sent on a mission to kill J’onn, a harmless alien. But instead of completing the mission, Danvers sacrificed his own life for J’onn’s survival, and ultimately the greater good.

But the most emotional storyline in “Human for a Day” is Supergirl’s, or rather, Kara’s, as she struggles with the unfamiliar feeling of being powerless. Maxwell Lord blasts Supergirl on television for not being able to come to the city’s rescue in the wake of the earthquake, so Cat plans a counter-campaign to support Supergirl, which leads to a real tear-jerker moment. Kara gets a pep talk from James — “No hero can save everyone, not even Superman. But a real hero never stops trying” — and decides to take his advice literally by stopping a convenience store heist. In a series of cuts between CatCo and the convenience store, Winn helps Cat set up a livestream to broadcast her pro-Supergirl agenda. Cat goes off-script and delivers an impassioned speech while Supergirl talks the man in the store into dropping his gun, giving James basically the best photo op ever.

Other parts of the episode are not quite so effective; James reveals a somewhat cheesy backstory about how his absent father inspired his love of photography. In one particularly heavy-handed moment he trails off and says, “… and then he didn’t come home.” In another, he turns subtext into text: “You don’t need real powers to be a hero.” Later, James exhibits some super powers of his own when he pries open two sets of elevator doors in order to save people from CatCo’s upper floors. Just as he looks set to plummet to his death in the elevator shaft, Kara regains her powers. She saves James, everyone in the burning building and the entire city. Supergirl is back.

The hero also shares a beautiful girl power moment with Cat Grant — flipping the narrative by telling her boss that she gave the people of National City hope when Supergirl couldn’t. “I know that you inspired them because… you inspired me.” But just as Kara is soaring away, on top of the world again, she’s brought back down to earth (literally) by her evil aunt Astra and her cronies. Next week’s winter finale looks set for an epic showdown between Supergirl and Astra. Although it’s pretty clear who will win (the clue is in the show’s title), this emotional roller coaster of an episode ensured we’ll stay tuned in to see what happens next.

“Supergirl” airs Mondays at 8 p.m. on CBS.

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