WARNING: If you don't want to know what happened in this episode, don't read this photo recap!
On Io, the pods with the protomolecule hybrids are launching, and from the Rocinante, Alex is trying to shoot down as many as he can. But he runs out of ammo pretty quickly. The pods have stealth tech and can't be tracked, but Avasarala is certain they're headed for Mars, where the damage could be catastrophic. Holden and his team heads into the Io station to look for a way to abort their course.
After Dr. Strickland devises a plan to get himself and Jules-Pierre Mao off of Io by using the children as human shields, he pays the Katoa hybrid a visit, where he inputs some kind of instructions.
On the Roci, Naomi and Alex show Avasarala that the UNN Agatha King was hit by a hybrid pod, and they can see the protomolecule already spreading its way aboard the ship.
Aboard the Agatha King, Cotyar is being knocked around in isolation as the battle rages on the ship. Suddenly, two people tumble into the room, fighting. The older man seems crazed, while the younger woman, Larsa, needs Cotyar's help (tethered as he is to his restraints) before she shoots the guy dead. She tells Cotyar that the blue substance is spreading on the ship, and it made the guy go crazy. Cotyar explains to Larsa about protomolecule, and seeing as she already has some spreading on her leg, she doesn't have a lot of time. But they can use that time trying to stop the protomolecule from spreading on the ship. Larsa is distraught, but she shoots Cotyar free of his restraints.
Cotyar grabs a spare vac suit and makes his way around the Agatha King, which is full of floating dead bodies and glowing protomolecule.
On Io, Draper sends Holden and company to go rescue the kids while she gets a hybrid to chase her in the other direction, despite Avasarala's warnings from the ship. Draper opens fire on the hybrid once she gets it in her sights, but its wounds heal, and soon, it's Draper running from the hybrid.
At the UN, Secretary General Sorrento-Gillis has been reeling from the news of the UNN mutiny and the hybrid launches. Anna shows up, and the two of them have their usual squabble about their past, before Anna pulls out her trump card: the communication Avasarala sent her, containing Errinwright's confession about his treachery.
The hybrid continues chasing Draper, who fires upon it and uses her boosters to help climb a ladder up a shaft. The hybrid's wounds again heal and, much like an alien and/or predator, it keeps pursuing her.
On Io, Holden finds the operation controls, and sees on a monitor Strickland trying to escape with some children. Amos and Prax run to catch him before he can escape the ship. Meanwhile, Holden sees that all controls for the hybrid pods are on the Agatha King, but he spots Jules-Pierre Mao on another monitor and heads out to force him to help.
Meanwhile, back on the Roci, Alex — who has been steadily freaking out about this impending attack on Mars — sets up the razorback so he can fly up to the Agatha King and divert the hybrid pods himself. Naomi tells him he can't go alone, so they leave the entire Rocinante in Avasarala's control.
On Prospero Station, the hybrid continues to chase Draper, who's using the thrusters from her suit, but it's powering down fast. After a thrilling chase, the hybrid gets the jump on her, and the two go tumbling down several stories.
At the UN, Errinwright is summoned by Sorrento-Gillis, who wastes no time in showing him the recording. Anna gets a little well-earned gloat in, but Errinwright isn't angry at her. He's furious at how spineless Sorrento-Gillis is. He rants about how he's only loyal to the last voice that spoke to him, and he'll blow whichever way gives him most political cover. He sneers that Earth deserved better. Sorrento-Gillis has Errinwright taken away, but immediately after, he dashes a hopeful Anna's hopes for a change of heart. "My legacy was going to be a catastrophic war with millions dead," he muses. "That's all on Errinwright now. Thank you."
Prax and Amos get to Dr. Strickland before he can launch his escape pod, which is bad news for Strickland. He plans to essentially trade the children't lives for his own, but when he recognizes Prax, he decides to play on that relationship and says he kept Mei safe. But Prax knows too much to believe it. He and Mei have an emotional reunion, but Prax then has Amos take Mei away for a moment, so he can take care of Strickland alone. Amos convinces Prax to stand down, though, saying, "You're not that guy." Amos is that guy, though, and as soon as Prax leaves the room, Amos finishes Strickland off.
Elsewhere, Alex and Naomi board the Agatha King and search for the pod controls. They come across a wounded Admiral Nguyen, who taunts them for their respective Martian and Belter heritage and tells them they'll never be able to stop all the pods in time.
Draper and the hybrid are both wounded on the ground, but while Draper's weaponized suit is pretty much out of juice, the hybrid makes its move. It peers over her, examining her, and she screams, "What are you waiting for?" But when the hybrid becomes distracted, she gathers up her strength to lift her arm towards the creature, and with the weaponry from her nearly-powerless suit, she blows its head off.
Back on the Agatha King, Naomi and Alex's work is interrupted by a communication from Cotyar somewhere else on the ship. He broadcasts that the Agatha King is infected with the protomolecule, and the only way he can defend against it is to overload the ship's reactor and have it essentially nuke itself. Naomi and Alex can't get through to him, even upon Avasarala's request.
Back on the Roci, Naomi has an idea for how to shoot down all the hybrid pods: go to Fred Johnson for help. He's got that cache of missiles Earth gave him last season, and Tycho is close to their flight path. Holden, Amos, and Alex are understandably skeptical of yet another Naomi plan to trust Fred Johnson, but she puts it up to a group vote, and they unanimously agree to do it.
Later on, Alex treats Draper's wounds in the med bay, Prax tucks Mei into bed, Naomi presents their offer to Johnson, Holden presents Jules-Pierre Mao to Avasarala as their captive, and Holden and Naomi finally reconnect in bed. Still, she tells him she can't stay.
While the missiles from Tycho take out the hybrid pods, the crash site on Venus begins to take a different shape. The crashed Eros begins to reconstitute itself as it emerges from the crater it made. Amos watches in disbelief from the monitor in the kitchen: "What the hell is that?"