It was obvious from the very first moments of "Supergirl" that the show's hero (and star) really likes being super. It's the greatest strength of the series thus far -- Melissa Benoist's Kara loves being a superhero, both because it means she can make a difference and because flying around and punching things really hard seems like fun. In "Livewire," the show continues in that vein, introducing a villain who really, really loves being a bad guy.

The best part -- it's not just when she's waving her electricity whips around. Brit Morgan's Leslie Willis is having a great time from the moment she appears, tearing into Supergirl on her shock jock radio show ("coming to you alive and wired" -- get it?). She's one step short of cackling, and as intended, it's infuriating. Leslie pushes every button she can think of, calling Supergirl an "abscessed tooth" and questioning the necessity of wearing both tights and a skirt since "no one is trying to get in there." Is Supergirl a lesbian? What's the deal with her bathing suit area? It's obnoxious and offensive -- which makes it a spot-on depiction of a certain brand of radio personality.

Despite the fact that Willis gets CatCo more than her share of attention (and ratings), the boss is none too pleased that Supergirl's the one getting attacked. Cat warns Leslie to back off, and when the latter understandably balks at having her content dictated, Cat demotes the broadcaster to traffic copter duty. This decision sets up Cat for a very difficult Thanksgiving, but before Willis makes her big transformation, we get some insight into the Danvers family dynamic.

While Benoist has gotten the lion's share of praise for her winning performance, Chyler Leigh is no slouch either. "Livewire" gives her a chance to stretch her wings a bit, since the already-intense Alex is wound even more tightly thanks to the impending arrival of her mother (former Supergirl Helen Slater) for the Thanksgiving holiday. That sort of family time can be stressful in the best of circumstances, but this episode shows, she's got even more reason that normal to be keyed up. Leigh and Slater have several terrific scenes together, nailing that uncomfortable family fight dynamic in a way that's mostly distressing but sometimes just a little bit funny (poor Winn!)

If "Livewire" has a weakness, it's to be found in these scenes. Despite the great acting that's going on, there are more than a few head-scratching moments and the occasional cringe-inducing line ("You've always been my Supergirl," as an example -- yuck). Alex approaches conversations with her mother with wariness and no small amount of anger, bewildered by the fact that she's often blamed for Kara's decisions without getting much of the credit. This is illustrated in moments both funny, as when Alex gulps wine through the first part of their ill-fated Thanksgiving dinner, and in moments that are somewhat less than subtle. At one point, Eliza tells Kara she looks beautiful in blue, then immediately turns to Alex and tells her she looks tired. So no, it's not subtle. But in a way, that, too, feels honest. We hear our loved ones through the filters of our own hurts, fears, and insecurities.

While the Danvers family drama takes up much of the episode, including a few flashes back to Kara and Alex's childhood and an episode-ending reveal, the real center of the episode is Leslie and her transformation into Livewire. When the traffic copter (or Cat Copter -- Cat Grant sure does love her name) flies into a storm, they, of course, need rescuing by Supergirl. Mid-save, however, Kara gets struck by lighting, and the energy passes through her and into Leslie -- a process that somehow turns her into an electricity-manipulating lunatic with a thirst for revenge. It also turns her hair a very trendy gray-blue, which lends this Livewire something of the look of the figure that originated in "Superman: The Animated Series" without the exaggerated hair (or leotard). If the early scenes of Morgan have some of Benoist's playfulness, it's once she goes full bad-guy that the fun really starts. Whether whipping electricity around like a cat-o-nine-tails or laughing through every television screen in Cat's office, she's having a great time being bad, and it's fun in the way that only the best villains can be.

She's so amped up (sorry) that it's no surprise that two great and powerful women need to team up to take her down. This unlikely alliance comes by way of Cat herself, who asks Kara to tell the FBI she needs to talk to Supergirl, then suggests they lure Leslie into a trap as soon as Kara gets a chance to change shirts. The plan works, thanks to a convenient water pipe, and the newly-arrived villainess ends up behind bars -- though given that the episode begins with Kara doing some light prison security, it's unclear exactly how secure these DEO facilities are. One can only hope she escapes soon. It would be great to see more of Morgan's gleeful maniac.

There's one last big development in this very "Supergirl" Thanksgiving, however -- it seems like Cat might be developing something of a moral compass, or at least letting down her armor a bit. Whether connecting with Kara briefly about her past or opening up about the complicated relationship she has with her own mother, this episode gives Cat -- and Calista Flockhart -- a chance to color with subtler shades. While the preening, Miranda Priestly drag has been a lot of fun, it'll be easier to take Ms. Grant if she's tempered with something that feels real, and honest. While it seems unlikely that all these changes will stick around, it's a serious step in the right direction, and we still get a few barbs here and there ("Congratulations, you have the wit of a YouTube comment"), Flockhart's willingness to play up the camp has been effective throughout the series thus far, but let's hope they keep letting her, like Supergirl and Livewire, be as big as she needs to be and as honest as she can.

One last note: CBS pulled the episode previously scheduled for this week, "How Does She Do It?," presumably due to this weekend's terrorist attacks. As of this writing, that episode has not been put back on the schedule. Personally, I didn't find the jump distracting, but Jenna Dewan-Tatum gave an interview to TVLine that details some of what happened that we might have missed. Check it out for a few tantalizing details.