Last episode ended on a serious cliffhanger/start of a fight, and “Not Kansas” picks up in exactly that spot. Supergirl and Mon-El, just back from their unexpected Argo City vacation, arrive just in time for a major fight with Reign in Lena’s lab. Mon-El shields Lena, as she creates the hoped-for cure, and Supergirl goes toe-to-toe with Reign, buying them time. Finally, there’s some decent teamwork, Reign gets injected, turns to weird burning-coal-like gas, and floats away, leaving behind a naked Sam, who asks for aspirin.

At the DEO sickbay, where I think the entire cast has ended up at one point or another, Sam recovers and gets a joyful reunion with Ruby. Alex looks on sadly, since she was really enjoying having Ruby around, and Sam mouths a silent “Thank you” to her. In the hall just outside, Supergirl asks Lena if she can make more of the Harenal, and explains the broad outlines of why she’s asking. Despite her recent, and justified, issues with Supergirl, Lena agrees and goes right to work. I swear, Lena is seeming more like the hero than Supergirl for much of this season.

Back at Kara’s place (which I’d still like to know how she’s affording since she doesn’t really seem to be Kara Danvers much anymore, so how’s she getting paid? Subsidy from James or the DEO?), she tells Alex all about her discovery of Argo City and her mother. Alex is floored. They talk about Kara’s early life on Earth, how each of them are feeling, and the fact that Supergirl is going to go back. It’s a nice sister bonding scene, and one of the better-written scenes on the show in quite a while that didn’t involve Lena.

At the DEO, there’s a big goodbye party (a running theme for the last few episodes of the season as we go) as Kara plans to go back to Argo and no one seems too sure about when/if she’s coming back. Mon-El asks her to find a way to get a message to the Legion for him, and she invites him along. So now two of Earth’s more powerful heroes are leaving. That seems like a great idea. There’s at least a hint that there’s a second goodbye over at CatCo and then she and Mon are off to the big city… the one floating in space.

They return to a warm welcome from Alura and the Council’s official greetings. Kara goes through boxes of her old stuff, because in a city with limited resources, why wouldn’t you keep old junk from someone you thought was dead around? She also meets her old friend Thara, her closest childhood companion now all grown up, married, and with an important job.

Somehow, Kara’s departure has ended all crime in National City, as a very bored Guardian shoots baskets and Winn commiserates over their coms. Finally, there’s a bank robbery call that falls into the “Be careful what you wish for” category. Guardian gets there just in time to save a cop’s life, but the shooter isn’t packing a normal weapon. Guardian’s so-far indestructible shield gets damaged by the shots, impressing everyone. The shooter gets away. This sets up for a weird and wholly unrealistic subplot, and yes, I’m aware I’m writing about a show where people fly and shoot lasers from their eyes.

Alex is unwinding listening to some opera, which she says Kara always hated. People really seem to be assuming she’s not coming back. She talks to J’Onn about music, and he talks about music therapy. M’Rryyn has some bad news that J’Onn doesn’t want to hear or believe. The “Martian Man-Father” then has a request to make that J’Onn really, really doesn’t want to hear about.

Winn is playing CSI with James’ shield and ends up having more bad news for J’Onn: the robber was using DEO special weaponry. James and Winn between them finally convince J’Onn about what they (Winn, actually) found, and the Director agrees it’s time to talk to the manufacturer. Up in Argo, Kara is enjoying being “normal” and even claiming she likes not being able to fly. Somehow I don’t believe that one. Mon runs into Val, the kid he cured last time, and all seems great. Until the nearby construction site falls apart and sprays shrapnel everywhere, nearly killing Kara and several bystanders. Given her life, and a glimpse of a mysterious cloaked figure walking away, Kara doesn’t believe this is an accident like everyone else. Alura thinks Kara is overreacting, but agrees to have Thara, the equivalent of a cop, look into it. For reasons that make no sense to me, Mon offers Kara his Legion Flight Ring. I guess because it’s her show?

J’Onn goes to interview the gun manufacturer, inexplicably bringing James with him. Because a gun maker is going to talk about a touchy subject more freely with a guy from the media there? Preston, the manufacturer, claims nothing is missing and no guns unaccounted for. Then he makes several ridiculous claims in a row. The first is that the DEO was incompetent enough to allow them the rights to manufacture a “civilian model” of the DEO weaponry. The second is that someone took one of those civilian models and converted it with a “bump stock.” Ok, I’m calling them out on that one. Bump stocks are in the news, especially after the horrific Las Vegas shooting. They allow a weapon to be fired like a fully automatic weapon, a “machine gun” as most people call it. What it does NOT do is let the bullets hit harder. So a bump stock couldn’t account for the bullets messing up Guardian’s shield. Some writer latched on to a buzz word and horribly misused it without doing his research.

Lena brings pizza to CatCo and finds James hard at work trying to research people who have bought this type of weapon. This turns into a debate about gun control, which anyone with a brain saw coming. Lena is actually at least somewhat pro-gun, but is reasonable about it. James invites Eve Tessmacher to join them for pizza, which was cool of him, and Eve then reveals a very surprising facet of her background they’d never even hinted at before.

Mon-El and Kara go to dinner with Thara and her husband. Aside from mentioning that Mon got his gizmo to contact the Legion, the meal mostly seems to emphasize how much everyone from Argo thinks Kara is paranoid. Kara sees the woman who was spying on her earlier, but she proves to be a local with a good reputation and no one believes Kara. The DEO investigation drags on as they lament the lack of a central gun registry.

Kara is at home enjoying the gardens when Alura brings the news that the construction incident was an accident caused by a faulty part. Kara doesn’t buy it. Alura talks about how hard it is to regain a sense of peace after traumatic events and they compare notes on their lives. Alura recommends that Kara spend a little less time worrying about others and take care of herself for a while.

The DEO plods ahead with their investigation and improbably manages to find the shooter. Checking his social media feed, they discover he’s about to become a workplace shooter, just to work in as many issues as they can for the episode. As they debate what to do, the shooter guns up and drives off. His former boss talks to J’Onn about the shooter’s outbursts, bringing mental health into it as well. J’Onn finally finds the shooter and manages to talk him down with no powers involved. That seems like a very Supergirl move, and shows he’s been paying attention to her.

Kara and Mon-El hang out in a big garden and talk about their past and their relationship. Things are just starting to get both serious and awkward between them when Cloak Woman tries to kill Kara again. Kara uses her borrowed ring to fly out of harm’s way and then capture the attempted assassin, who proves to be the same local woman again. Thara is shocked when they do the big Scooby-Doo unmasking and asks the woman why. This is when they learn about a whole new faction in Argo no one knew about, and a surprise reveal of who the leader is.

Then the show gets stupid. I’m sorry, there’s no other word for it. It’s no shock that many, if not most, of the people in the entertainment industry tend to be liberal and think along the same lines. I get most of them are anti-gun and I don’t disagree on many fronts. But J’Onn’s sudden announcement that the DEO, as a government enforcement/combat agency, will no longer be using lethal weaponry, is ludicrous at best. I doubt he has the authority to do that, and how in hell are they supposed to fight the menaces they face, especially since Winn’s promised “non-lethal tech” isn’t even designed, let alone built, yet? Many of the agents react predictably to this stupidity, and it looks like the DEO is going to be shorthanded for a while.

Lena and Eve study the Herenhal and talk about its potential to do amazing things. J’Onn goes home to accept some of the things his father was telling him. Alex reflects on her future and does some research on something she’s been considering for a while now. Coville makes a new friend as Kara and Mon-El find out they should have gotten LoJack.

What I liked: I’m glad we’re getting to see Guardian in action more, finally. Mon is a quiet, strong presence on the show, so much better than his earlier, clownish incarnation. I get why Kara would want to go back home to a place and people she thought didn’t exist anymore.

What I didn’t: Most of the rest. Why would J’Onn bring James along on an investigation? As explained above, the bump stock was misused. I don’t understand how Supergirl leaving apparently stopped crime in National City for a while. J’Onn’s decision to essentially disarm the DEO made no sense at all and was entirely unrealistic.

I know this is a tense topic these days, so let me be really clear here: I am not a member of, nor believer in, the NRA. I’m also not a member of any anti-gun group. It’s a complex issue on a lot of fronts when you look at actual concrete, detailed solutions. I agree America’s gun laws, and the entire system around them, needs to be reworked, and I understand the writers wanting to address it. I think they did so very badly here, with the subtlety of a jackhammer.

I’m giving this a low 2 out of 5. The CW can do better than this. I hope.