Pluribus Episode 9: What is signal 8613.0? The maritime frequency that might destroy the alien hive mind

Vince Gilligan’s sci-fi brainchild, Pluribus, wrapped up its Season 1 on December 23, 2025. The finale, titled La Chica o El Mundo (The Girl or The World), delivered a cliffhanger setting the stage for Season 2.

Apple TV aired it at 9 pm ET/6 pm PT, and it became the streamer’s most-watched show, surpassing Ted Lasso and Severance. The discovery of 8613.0 kHz frequency in this Episode might just be humanity’s ticket out of the hive mind the aliens created.

The finale put Carol Sturka (Rhea Seehorn) and Manousos Oviedo (Carlos-Manuel Vesga) into the deep end. All season, they have been butting heads, but now they are at a do-or-die fork in the road, picking between what they want for themselves and saving all of humanity. Carol finally swings back to Manousos’s corner, dragging along something she ominously calls an “atom bomb”.

The Pluribus episode finally drops breadcrumbs about how they might break the Joining, and it all circles back to Manousos’s “aha!” moment with the 8613.0 kHz signal.

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Decoding signal 8613.0 in Pluribus Episode 9

In Pluribus, 8613.0 kHz shows up as Manousos is stranded in Paraguay, spinning the dial on his radio. He is hoping to catch some chatter, but stumbles onto this totally bizarre, looping signal. You first see this in Episode 6, HDP, where Manousos scribbles it in his diary with a bunch of question marks. He has no clue what’s going on at that point.

Move forward to Pluribus Episode 9, and things start unravelling. Manousos starts playing around with the frequency. Every time there’s a loud noise that snaps the Others out of their zombie groupthink, he notices the radio signal clears up, it gets more intense, more “loopy.” Now he has a theory: if the tweaked RNA is rewiring people’s bodies, then this 8613.0 kHz is the mind control software, just blaring on repeat across the globe, keeping everyone stuck in the hive mind.

Turns out, the answer was right there from the start in the opening credits, with the trippy wave pattern and little dots syncing up. That’s the frequency in action. The show runners were literally flashing the brainwashing tech at us and nobody clocked it until later. Someone on Reddit was even quoted by Esquire as saying:

“The intro is showing us that the Hive needs that external broadcast to stay synced.”

Back to Episode 9. Manousos tries blasting the 8613.0 signal at one of the Others after shocking the group out of their shared consciousness with a jumpscare. He slaps the radio onto his guinea pig’s chest, hoping to break the hivemind connection. The Others start seizing, Zosia is convulsing, and it looks like millions of people could be dying from this. So, Manousos just might have invented mass psychic warfare with his little radio stunt.

The real-world science: Maritime and aviation frequencies

In reality, the frequency of 8613.0 kHz is situated in a strange place in the radio spectrum. The frequency is found on an unusual but not entirely nonexistent stretch of the spectrum, where it is hidden between marine and air traffic and thus out of the reach of amateur radio operators. International telecom standards state that the range of 8101 kHz to 8191 kHz is allocated for simplex maritime radio use in 3 kHz steps, where it overlaps with fixed/mobile service.

Maritime HF (High Frequency) communication takes place in various bands that are specifically set apart for ship-to-ship and ship-to-shore communication. These frequencies carry all sorts of USB voice chatter, data, FAX transmissions, FSK, RTTY, and more. Also, there are weather and emergency broadcasts to ships at sea. And the 8 MHz maritime band specifically allows your signal to skip across oceans, bouncing off the ionosphere to communicate over long distances.

Now, picking 8613.0 kHz for a mysterious broadcast is genius. Maritime frequencies are under constant surveillance for safety reasons, so if you want to plant a signal that blends in, barely raising an eyebrow, you couldn’t ask for a better spot. The fictional 8613.0 kHz signal has been positioned close to actual emergency communications infrastructure since search and rescue (SAR) operations have been utilizing nearby frequencies that also include 8364 kHz USB for voice SAR onsite coordination and communications.

These HF frequencies can travel thousands of miles by refracting off layers of the ionosphere. It’s perfect for ships, but if you are spinning a yarn about a worldwide hive mind like Pluribus, then you would want a frequency that could reach every corner of the globe.

Where does all this lead us?

At this point in Pluribus, we know two things: 8613.0 frequency and Kepler-22b. Back in Episode 8, Charm Offensive, Zosia tells Carol that the alien signal that kicked all this off came from Kepler-22b. That’s not a made-up planet. NASA actually found it in 2011, and it’s 640 light-years away in Cygnus. And it resides in the habitable zone, orbiting a star that’s like our Sun. It’s unclear whether it has any kind of life form.

Scientists call Kepler-22b a “water world,” and it’s double the size of Earth. In Pluribus’s story, this watery planet sent out a mutant RNA code that rewired people’s brains, and now the Others are out here putting together a giant space antenna to beam the “virus” right back out into the galaxy.

Now, in Pluribus Episode 8, they dig into how all this works, and it’s very important in giving the proper understanding of the 8613.0 frequency. Zosia, in her talk with Carol, opens up the transmission of the Others and, in doing so, she calls it “unconscious” and “homeostatic, like breathing,” reflecting the others’ and the world’s radio frequencies. Nevertheless, the 8613.0 frequency seems to be the conscious technological backbone of this biological communication network.

So, you have got two layers going on: the RNA alters people’s biology so they are open to this hive mind, and the 8613.0 frequency keeps everyone’s brains on the same channel. This opens up the opportunity of supposing that certain survivors, for instance, Carol and Manousos, could possess some kind of mental immunity. Not only are they dodging the RNA alteration, but they are also jamming the hive mind’s frequency.

In the Pluribus finale, Manousos is nose-deep in antenna books, specifically the idea of “standing waves.” The book explains that when you transmit a radio frequency through an antenna, the current doesn’t just go straight. It wiggles back and forth, making signature wave patterns. There are spots where the signal totally drops off; those are called “nodes.” And other spots where the power is elevated all the way up; those are “antinodes,” or sometimes just “loops.”

Now, when Manousos scribbles the word “loop,” he is creating a theory: the infected ones (the Others) are stuck inside one of these frequency loops, right at the spot where the signal is blasting at full force, the antinode. That means:

Standing wave pattern: The signal behaves like a predictable wave going up and down.

At the loop/antinode: Signal is of highest intensity = hive mind is totally synchronized.

At the node: Signal goes down to zero = possible interruption in synchronization.

So, what’s his big question? He is wondering if there’s a way to drop the frequency to a dead spot (the node), where the signal just fizzles out. Basically, could he get the Others out of their hive mind by cutting the connection at its weakest point? That’s what he is puzzling over, and that’s what might be the key to this mystery afterall.