The most recent episode of The 100, “The Four Horsemen,” ended with the cliffhanger that Luna’s Nightblood might be the key to beating the effects of the impending nuclear radiation. While the show played it as a big moment — complete with Clarke dramatically repeating the Season 4 tagline and newly discovered cult slogan “From the ashes, we will rise” — it might have been confusing for those who haven’t watched Season 3 in a while. And even if you have, the Nightblood mythology was always a bit murky. Here’s a refresher.

A Nightblood is a descendent of Becca, the person responsible for A.L.I.E. and therefore, the end of the world the first time around. Horrified by what her creation did, Becca made a second version of the A.L.I.E. program — or the Flame. In order to be able to withstand injecting the Flame in her neck, Becca injected a dark substance in her blood that altered her genetics. All her subsequent descendants have had dark blood.

Up until this point in the show, a person’s status as a Nightblood has meant that the flame can be injected in their neck without self-destructing and killing them. In Season 3, this is why Clarke injected herself with the Nightblood Ontari’s blood before she took the Flame.

It’s also why Clarke and Bellamy visited Luna in Season 3, as she is rumored to be the last Nightblood, and they wanted someone sane to become the next commander and stop A.L.I.E. Unfortunately, that visit didn’t work out because Luna refused the Flame, and A.L.I.E. infiltrated her peaceful hideout.

But in Season 4, when Luna showed up in Arkadia suffering from the deadly symptoms of Acute Radiation Sickness, Clarke later discovered that she was inexplicably able to fight it off. Apparently, there’s more to being a Nightblood than compatibility with a computer chip.

Luna, Clarke, and Bellamy in "The Four Horsemen"
Luna, Clarke, and Bellamy in "The Four Horsemen" 

Luna never wanted to be in the spotlight or at the center of the action, but the choice has been taken away by her genetics. The Season 4 slogan is “From the ashes, we will rise,” and the impetus to their rise is in the blood. While it seems that the show moved on from its former mantra of “blood must have blood,” it hasn’t moved as far as you might think.

The 100 airs on The CW on Wednesdays at 9 p.m.

Photos via The CW

Lauren's writing has appeared on The Huffington Post, Page Views at The New York Daily News, and 20SomethingReads at The Book Report Network. She has also interned at The Overlook Press and Cosmopolitan. A Dartmouth grad, she lives in Brooklyn.

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