Lets start there: We learn theres a nuclear reactor powering Sanctum, and its not doing well.
He thinks he can fix it he cant, and they both end up dead.
Temperatures are rising, and if it hits, 1,500 degrees, Bye, bye, Sanctum.

Credit: Dean Buscher/The CW
Raven has a plan.
The rods are in the inner room, where radiation levels are incredibly high.
They will need to be pushed down by someone who can handle that amount, a.k.a.
Luckily, they have three: Clarke, Murphy, and Emori.
Theyll also need four people with welding experience to help fix the burst pipes.
Cut to the prisoners, who are grumbling about their arrangements.
Murphy and Emori give her side-eye, but she says thats the only way to get them to agree.
But they cant think about that for long: Emori goes into the radiation room to lower the rods.
She has a minute to get all four down, and she does it with no time to spare.
As soon as she gets out of decontamination, she starts vomiting.
And then Murphy does, too.
Hatch asks her whats going on, and she says its xenon gas making them dizzy.
Hatch tells her he needs more nitrogen, and when Murphy takes it in, Raven locks him in.
Go be a cockroach, she tells him.
As he helps Hatch weld the final leak shut, we learn the prisoners story.
Hatch is no dummy: He knows xenon gas isn’t taking out his fellow prisoners.
He also knows that if they dont finish, his wife wont survive either.
No matter what, we get this done, he tells Murphy.
Oh, and his wife?
Her name just happens to be Nikki.
HER NAME IS ACTUALLY NIKKI.
The writersmusthave done this on purpose, right!?
Anyway, he tells Murphy they were bank robbers … until they turned into murderers.
Nikki shot two cops during a robbery, so they decided to execute the hostages to eliminate witnesses.
Nikki and Paolo were diamond thieves and murderers.
Raven is devastated as she drags all the bodies out.
Welcome to the world of gray, Murphy tells her.
And just then, Nikki comes in and sees her dead husband.
She snaps and beats Raven to a pulp.
I have a feeling weve got a new rivalry on our hands.
But lets talk about our main rivalry of the episode: Clarke and Russell.
Theyre being generous and letting him choose his own method of death for that evening.
But his followers dont, and thats why theyre planning to do something to stop the execution.
Jordan gets wind of it and tries to convince Russell to tell his people to step down.
Indra speaks for Madi, saying the commander needs volunteers, but theyre not buying it.
Indra says shell go find Madi, but Gaia decides this is the moment to come clean.
She has faith in her people to handle the truth, but that faith may have been misplaced.
When she says there is no longer a commander, Wonkru demands to know why.
Well, that angers Sangedakru, who says that he was their greatest commander ever and storms out.
Wonkru falling apart is not great.
If a revolt breaks out over Russells death, theres no longer a united front to stop it.
Because of this, Indra says they should let Russell speak to quell his own people.
Russell is again all about peace.
He tells his people to let his death heal this place and not to take revenge.
Either we live together or die apart, he says.
(I MEAN.)
He doesnt get to finish his speech, though, because someone from the crowd shoots him.
Jackson rushes him to medical to save him.
And Indra is all business: She tells Clarke that they cant execute him now.
If they did, the faithful would have a martyr and Sanctum would implode.
(My kind of medicine!)
She whispers, You were right about Jordan.
He did exactly what you predicted he would.
Getting shot to thwart his own/Russells execution was always his plan.
But one things for sure: Sangedakru is going to be psyched to have their long-lost commander back.