In "Ace Reporter," "Supergirl" returns from its brief hiatus and does something really novel: it focuses on Kara Danvers.

For a not insignificant part of its second season, "Supergirl" has oddly sidelined its titular heroine, choosing to focus instead on her love interest, sister, and friend. That's not a slight to Mon-El, Alex, and Lena, all of whom are interesting characters played by terrific performers -- Katie McGrath gets her share of oxygen in this episode as well, and she remains a delight -- but by making Kara a force in other people's lives, rather than a compelling character in her own right, left the show with an odd imbalance. Melissa Benoist isn't just playing the title character. She's the shows's greatest strength, and turning her into something of a plot device never quite worked.

Not so with "Ace Reporter," and while it's still a flawed hour, it's an entertaining one too. The hour begins with Kara gleefully flying to the DEO -- always such a pleasure to see a superhero enjoy their superpowers -- only to arrive and find out there's nothing to do. (Alex's only line in the episode is a good one: "Thursday morning knife practice.") At a loss, she heads home to try her hand at some baking sans oven mitts, an activity that gets interrupted when Lena shows up, in need of a friend buffer for an ex-boyfriend's fancy tech presentation.

Kara brings her reporter notebook -- a lucky thing, as Snapper's there, raring to heckle her -- and as she and Lena take their seats, out walks Ravi! To be more accurate, that's Jack Spheer, Lena's aforementioned ex, played with just the right amount of dastardly ambiguousness and quite a lot of romantic gusto by "iZombie" star Rahul Kohli. With some help from his CFO (played with a bit of twist-ruining wryness by Claudia Doumit of NBC's "Timeless), Spheer demonstrates his "fourth medical miracle: nanobots. Anyone who doesn't immediately know these things will go bad has never seen a movie or read a comic before.

With that suspense out of the way, we wait to see how and when the 'bots will turn. As the two former lovebirds banter, a strange man approaches Kara, the only reporter he trusts, and tells her to meet him in a parking lot that night. Because she's the Girl of Steel, she does, and as the stranger begins to whistleblow on Spheer, the 'bots show up to blow up his car. Kara bursts out, clothes on fire, unable to save someone who died right before her, and it's a striking moment and a great piece of acting. From here she tears right on through to the episode's final moments. No motivation like feeling helpless for Kara Danvers.

Our intrepid blogger heads to CatCo to see if James will submit a Freedom of Information Act request for her, a possibility killed by Snapper in about a second. It's not a wasted trip, however, Kara overhears that Snapper's got a source of his own. She shows up in time to save Snapper, but not the source, and heads home, distraught, only to have Mon-El tell her that Lena's at dinner with the supposed big bad 'bot handler at that very moment.

As stated in previous recaps, Chris Wood is very good at his job, and is even better when he's a foil for Kara, rather than a shadow protagonist. Here, he puts all that oddball charm to good use, pointing out that Kara's plan to bust in on this date might be considered stalking and saying "Mike" about 97 times. Lena's bewildered but not angry at Kara's intrusion, though her attempt to grill Spheer goes awry when he turns the question into a chance to profess his deep feelings for Lena. Mon-El suggests they leave, gives Spheer a super awkward hug on the way out, then reveals that he stole Spheer's security pass. Off they go to break into a fancy office.

 

Related: Rahul Kohli Brings Tech, Romance & iZombie to Supergirl

 

It's a cute scene in which they banter before finding a video that stamps all the cute right out of them: Spheer's injected himself with the 'bots, and now is the 'bots, and that makes him a murder-'bot. Kara inserts a flash drive to swipe the file -- way to carry that on you, Kara, that's actually very practical -- and Spheer goes all distant and weird on Lena, who he was just smooching. Kara and Mon'El run just as a 'bot cloud flies in through the window, reforming as a suspicious looking Spheer.

It's all a big head-fake, of course. After warning Lena to stay away from Spheer, which of course she doesn't, Kara goes to drop off all her research with Snapper, recognizing that Snapper's massive platform (and the fact that he's a career journalist) will get the truth to more people than Kara Danvers Dot Com ever would. He lets slip that the CFO might be guilty too, and Kara realizes what everyone else watching suspected from early on -- there's a twist.

Cut to Lena, confronting Spheer, who's completely bewildered until aforementioned CFO Beth Breen turns his brain off with a mind-controlled earpiece. Citing her bottom line, Breen commands Spheer to kill Lena, and Supergirl shows up just in time. Lena then tells Supergirl to distract the bots and kicks the ever-loving crap out of Breen. Just before getting a sharp elbow to the throat, Breen lets slip that if Lena destroys the mainframe -- the only way to turn off the 'bots now controlling Spheer and close to killing Kara -- she'll also kill the man she loves. With an agonized apology to Spheer, who begs for her to do it, Lena flips the switch, and Spheer dies, gasping.

Not everything in this story works, but the two big scenes that follow sure do -- first Lena tells Kara that her family doesn't handle loss well, and when she emerges from her grief, she doesn't know what she'll be. Kara promises to be there, and it's a lovely shared moment between two people with lives marked by tragedy. Then Kara gets her job back. Having Ian Gomez back as Snapper is good, but having him back in the role of begrudging mentor is even better.

Then Teri Hatcher shows up and offers Lena a business proposition. This can't end well.

You'll notice there's no discussion of the Winn/James/Lyra subplot above. That's because it's not very good. Here's the short version: Lyra is now on team Guardian and James told Winn he's his best friend. That's it. That's what happened. Next week: something that looks totally nuts. If "Supergirl" dives into the horror genre, that'll be can't-miss stuff.

Airing Mondays at 8 p.m. ET/PT on The CW, “Supergirl” stars Melissa Benoist, Mehcad Brooks, Chyler Leigh, Jeremy Jordan, David Harewood and Chris Wood.