Relationships fuel The 100. The various “ships” that fans passionately support are obviously a big part, but when it comes to The 100 itself, every relationship matters — not just the romantic ones. Lincoln and Octavia were lovers, but they were somehow more than that, too. They were family. Clarke and Lexa were simultaneously rivals, allies, and lovers. The 100’s suspense and thrills are built on the foundation of these complex, evolving relationships that give stakes and meaning to the drama.
In one of its intersecting plotlines, “The Four Horsemen” focuses on one of the series’ best relationships: Indra and Octavia. Octavia Blake has had one hell of a character arc since the pilot, and Indra has been just as formative of a presence in her life as Lincoln was. After becoming Indra’s second, Octavia committed herself completely to the ways of Trikru. She’ll always care for her brother, but she has pointedly distanced herself from her people. Her evolution into a warrior comes to a head in this episode, when Roan informs Indra of Octavia’s new nickname: Skairippa, which means death from above. Indra has created a killer.
Obviously, Indra has mixed feelings about that. Indra and Octavia’s relationship extends beyond friendship into something more maternal, and that dynamic comes to the surface with the introduction of Indra’s actual daughter. As the new Flamekeeper, Indra’s daughter steals the Flame from Roan. Octavia follows her, prepared to kill her over it, as Roan’s possession of the Flame is the thin thread holding the coalition together, but Indra intervenes. In this one quick scene, we get a lot of backstory and context for their relationship: Indra wanted a daughter who followed in her footsteps as a war leader and warrior, but instead she got a religiously devout child who goes on spiritual journeys to find nightbloods and preserve the Flame’s power. “Looks like you found your perfect daughter,” the girl spits at her mother, referring, of course, to Octavia. The 100 develops their relationship from the other side, too: Octavia wouldn’t be who she is today without Indra, but the latter doesn’t merely exist to push along a character arc. Indra has her own backstory, her own reasons for taking Octavia under her wing.
Another one of the show’s complex relationships also gives weight to this episode: Abby and Raven. Ever since their days of secretly plotting to escape to the ground in season one, Abby and Raven have shared an intricate bond. They’re friends, but they’re constantly challenging one another. They need each other, and yet they’re constantly getting in each other’s way. In “The Four Horsemen,” Nyko and Luna arrive at Arkadia with a group of sick Grounders. The radiation is wreaking havoc: Fish are dying, and people are already showing signs of radiation sickness. Nyko and Luna seek Abby’s help, but Raven won’t let her have the radiation pills that could save them. Though Raven always does things her own way, when she has a mission, she sticks to it, no matter what. Her mission right now is to prepare the Ark for the end of the world, so everything must be rationed carefully. She doesn’t back down when Abby fights her on it.
So Murphy takes things into his own hands. Now, I am far from a Murphy fan. It’s easy to hate Murphy, and like most viewers — and even other characters on the show — I often dismiss him. But for as annoying as Murphy is, he’s actually a fascinating character. He’s just as developed as the rest, and even his most annoying actions come from an emotionally honest place. It has always been clear who he is. But if Richard Harmon weren’t so good at playing the character’s angst, I bet Murphy would have gone long ago. It often seems like the writers don’t know quite what to do with him. His characterization is strong, but his story lines are almost always weak and his relationship with Emori has never been particularly compelling. “The Four Horsemen” makes a weak attempt to rectify that by making Emori jealous of his connection of Ontari, but it ultimately adds nothing.
When Murphy decides to return to Arkadia to steal some food for their journey, things finally take an interesting turn. After overhearing Abby and Raven arguing, Murphy steals the pills and gives them to Abby so she can treat the Grounders. On the surface level, this action signifies a notable change, an act of selflessness for a character defined by self-preservation. But the episode is explicit about the action’s underlying significance: His father was floated on the Ark for stealing medicine for Murphy when he was sick with the flu. As always, The 100’s characters are motivated by their pasts and by the people who helped shape who they are.
“The Four Horsemen” also adds a new arm to the beast that is this show’s mythology. Jaha informs Bellamy and Clarke of Bill Cadogan and the Doomsday Cult, a group of fanatics who took drastic precautions in the weeks leading up to the bombs that first destroyed the world. Cadogan preached of salvation, which is of course irresistible to the perpetually salvation-seeking Jaha, and so he, Bellamy, and Clarke go on a search for Cadogan’s bunker. They find it, but it’s full of corpses. There goes their hope for a last-ditch answer to their prayers. On The 100, there are rarely convenient solutions. Every time characters think they’ve found the answer to their problems, something goes wrong. It’s a savvy formula, meant to keep the story exciting and the conflict in constant motion, pushing the characters to resort to truly devastating measures.
Although the bunker didn’t pan out, the Doomsday Cult isn’t quite irrelevant yet. Abby’s Grounder patients all die except for Luna, whose symptoms mysteriously fade away. Suddenly, the key to surviving radiation becomes clear: nightblood. No detail is insignificant on The 100, and I’ve been waiting for the black blood that oozes out of the Grounders’ elite warriors to mean something more than just their ability to host the Flame. Sure enough, it does. Nightbloods can survive radiation sickness, which helps explain where Grounder populations came from in the first place.
I’ll be honest: It has been a long time since I thought about The 100’s title. Though the original 100 teen criminals’ arrival on the ground sparked the ongoing conflict for the series, the number itself hasn’t been relevant for a while. By the end of the second season, less than half of the 100 lived. With Alpha Station, Farm Station, and all the Grounders clans gradually becoming a bigger part of the story, the narrative isn’t dominated by the 100 anymore, but rather split among the shifting groups involved in the endless war on the ground. But in season four, The 100 has ascribed new meaning to its title. Faced with the impending radiation, Clarke is tasked with deciding who gets a spot on the Ark at the end of the world … and there are only 100 spots. Throughout “The Four Horsemen,” she’s working on the list, pressured by Raven to finish it quickly.
At the end of the episode, Clarke gives Bellamy the 99th slot. And Bellamy writes her in as the 100th. These two could write the book on complicated relationship dynamics. They have made some of the hardest decisions of their lives together. They pulled the lever that radiated level five of Mount Weather together. They don’t always see eye to eye, but they are co-leaders through and through. When they opt to save each other, they do so for selfish but well-established reasons. Like Abby and Raven or Octavia and Indra, they need each other.