Wow. I think it's safe to say that The 100 Season 4 Episode 12 is one of the show's best installments ever. At the very least, it's undoubtedly a game changer.

By the end of it, Kane and Jaha had finally agreed upon a method to choose the people who would remain in the bunker, while several of our main characters were stranded outside – and headed to space.

Overall, I think that The 100 does its best work when the narrative isn't spread too thin. I love that we have a fully fleshed out world, but the show's best moments tend to come at the end of respective seasons, when the storylines have been condensed to just one or two main plot threads.

In this case, it was split fairly evenly in two: the group in the Second Dawn bunker, and the group that set out to rescue Raven from Becca's island. So let's get into the nitty-gritty.

The idea that Clarke, Bellamy, Murphy, Emori, Monty, Harper, Raven, and Echo are heading to space is a great way to bring the show full circle.

Back on The 100 Series Premiere, they were preparing to come down to earth 97 years after leaving it. Now, they're heading back up and it's only been – what? Less than a year on the ground?

Time sure flies when you're having fun constantly fighting every conceivable threat in order to survive!

"The Chosen" was filled with memorable moments and outstanding performances. I was particularly moved by Henry Ian Cusick's performance, as Kane grappled with his eventual decision to gas his people in order to pick and choose who would live and who would die.

This is how we save our people.

Kane

• Permalink: This is how we save our people.

So much for that lottery idea. In the end, Clarke's list from earlier in this season made its reappearance.

Ian's work on "The Chosen" was an award winning performance if I've ever saw one. It legitimately brought me to tears – there was such raw pain (and even shame) in his eyes.

Kane's decision was precipitated by a compelling face-off with Jaha, who had a different idea about how to handle the tough decision – to not make it at all.

I've always said that, love him or hate him, Jaha is one of the show's most well-developed characters (much like Murphy). He went from ruthlessly willing to sacrifice his own people to ensure some portion of humanity survived, to essentially the complete opposite – now, he prioritized his own group's survival over the good of humanity.

The argument – voiced by both Jaha and Jeff, a man who worked with Jaha to start up the incipient Skaikru riot – that the Sky People somehow "deserved" more spots because they were more technologically advanced than the grounders is an incredibly prejudiced one.

Obviously, knowing the technology doesn't mean that they deserve to survive any more than the grounders. In fact, only a handful of Skaikru was even necessary to keep the machinery up and running – I'm sure 75% of those people had no hand in running the machinery.

I'm really glad that mentality didn't win out in the end, though I certainly wasn't expecting Jaha would be willingly talked down by Kane. He seemed set on his plan to rally Skaikru to fight for survival.

The time for diplomacy is over, Marcus. Now, either you lead us into battle or get the hell out of my way.

Jaha

• Permalink: The time for diplomacy is over, Marcus. Now, either you lead us into battle or get the hell...

Surprisingly, Kane appealing to Jaha's better nature and his salvation (aka, character growth) managed to work. It was an incredible scene between Ian and Isaiah Washington.

Also outstanding: the scene between Abby and Kane earlier in the hour, when Abby informed him of her decision to sacrifice herself in favor of someone else living. After everything she'd done, she doubted that she was worthy of survival.

Kane wasn't willing to let Abby go, which worked out perfectly for him when he and Jaha decided to gas everyone to prevent all-out war between Skaikru and the grounders. Unfortunately, I doubt that Abby will look too kindly on Kane's decision.

But hey – five years is a long time. Plenty of time for Kane to win Abby's forgiveness back. Also, given that she opened the bunker doors partially just to save Kane, she should understand the whole "going to any lengths necessary to save the person you love" thing.

Because, oh yeah, Abby finally told Kane she loves him. It was a great, sweet moment amidst all of the soul-crushing sadness!

The other portion of the bunker narrative focused on Octavia. She's reckoning with how to be an effective leader, but I appreciate the fact that she's visibly struggling with the hard choices a leader needs to make.

Her decision to open up the bunker to everyone and to equitably and fairly divide up the available space was, rationally and logically, the correct one.

But Octavia is a human being, not a robot and not someone like Clarke who seems to be more of a natural at making tough calls. O couldn't sacrifice all of her people to death so easily.

Indra is still being a pretty great right-hand to O, though, even offering to "take care of" the Skaikru problem if Octavia found it too difficult. And let me just say again how much I love the fact that the grounders have just fallen into line behind Octavia.

As a minor point, I also loved that Octavia adapted Bellamy's signature "My sister, my responsibility" line:

Indra: I'll do this for you.
Octavia: No. My people, my responsibility.

• Permalink: No. My people, my responsibility.

The other section of the hour focused on Bellamy, Clarke, Emori, and Murphy setting out to retrieve Raven from the island. As Abby said, Raven was essential personnel and guaranteed a space in the bunker.

For Bellamy and Clarke, they were rescuing Raven because she was their friend. Those two shared an excellent goodbye scene with Abby, which takes on a whole new level of poignancy now that we know Clarke will likely not see her mother for five long years.

Clarke, listen to me. I told you there were no good guys. But that's not true. There are. You are.

Abby

• Permalink: Clarke, listen to me. I told you there were no good guys. But that's not true. There are. You...

At least they ended things on a very good note.

Also, this happened:

Abby: Take care of each other.
Bellamy: Yes, ma'am.

• Permalink: Abby: Take care of each other.

Yep. Bellamy "Yes, ma'am"-ed Abby. I can't quite articulate why that was such a satisfying moment – but it really was.

For Murphy and Emori, going to save Raven wasn't an altruistic act. As expected, they figured they would not get spots in the bunker (their odds weren't good under either the lottery or Clarke's list scenarios), so they intended to ride out the death wave in the island bunker.

It was a decently good plan, despite the fact that it wasn't equipped to be survivable for five years.

Echo also joined the ragtag group on their way when she stepped in (aka, rode up with bow and arrow on an irradiated horse) to save the foursome from grounders who intended to steal their suits.

Can't say I expected to see Echo again after Octavia re-banished her, but she does prove useful in a pinch. Also, I'm eager to see how she'll adapt to living in space – assuming Raven gets them there. (Of course she will; she's Raven.)

Bellamy: Raven, we need you to get us off the ground before the death wave hits. What do you say? Can you do it?
Raven: What do I say? I say that death wave can kiss my ass.
Clarke: Good. It's settled. We're going back to the Ark.

• Permalink: Good. It's settled. We're going back to the Ark.

Interestingly, Bellamy was willing to sacrifice Raven when he thought that Clarke's nightblood might be effectively working to counteract the effects of the radiation when she gave Emori (whose suit was torn) her own suit.

They didn't get far enough to see whether the nightblood does actually work – Clarke was showing symptoms of poisoning before Harper gave her the extra suit, but so was Luna before she healed herself.

Somehow, I'm still convinced that the nightblood will prove an effective solution in the end. It would be a neat twist, at least, and would mean that a five-year time jump for The 100 Season 5 isn't entirely necessary.

But who am I kidding? An extensive time jump of any kind would be a great way to reinvigorate the show. I love me a good time jump , and it will be especially compelling to see how Bellamy does after five years of not seeing his sister and Clarke after five years not seeing her mother.

Stray thoughts:

• Miller's dad wrote his son's name instead of his own for the lottery. I teared up instantly.

• That Miller and Jackson hug. Yes.

• Jaha picking up unconscious Ethan got me right in the feels. The idea of a surrogate son for Jaha, after the loss of Wells, is really compelling. But given that Isaiah Washington isn't set to appear in The 100 Season 5, I guess that's not happening. I'm wondering how he's going to be written off. I was sure he'd be killed off in this installment's riot (which didn't end up happening).

• Octavia rescuing Niylah from the rioting Sky People was great! I love Niylah, so I'm glad she's guaranteed survival. 

• It also may have made me ship those two a little bit. Did you see Niylah touching Octavia's hand when she told her she'd never forget what she did for her? Plus, Niylah's not going to see Clarke for like five years, so that's plenty of time to move on.

What did you think of "The Chosen"? Share your thoughts by commenting below, and remember that you can watch The 100 online anytime here at TV Fanatic.

Caralynn Lippo is a staff writer for TV Fanatic. Follow her on Twitter.