What's the virus in The Boys season 4? Neuman's Supe-killing substance, explained

Warning! This article contains spoilers for both The Boys season 4 and Gen V season 1. If you've yet to catch up, and don't want to know anything that happens, turn back now!

Last week, The Boys season 4 featured references to a bunch of Gen V characters, from Marie, Andre, Jordan, and Emma, AKA the Godolkin 4, to Tek Knight. Now, with episode 5, it's doubled down on the connection between the two shows, with cameos from Cate and Sam, and by introducing the Supe-killing virus first seen in the spin-off.

"I don't think it's a spoiler to say that, by the end of season 1 of Gen V, there's a handoff to season 4 of The Boys," creator Eric Kripke previously told Entertainment Weekly. "When they were breaking the virus storyline, they just had to be in regular communication with me in my room to understand, "Is that a thing out in the world that'll be helpful to us or is it going to f*** us?"

Now, if you've not yet watched Gen V (and who could blame you, honestly, given that Kripke claimed you wouldn't need to not so long ago), you might be a little confused as to what the substance is, and how it came to be. Below, we dive into all of that, to get you up to speed as the two Prime Video shows continue to crossover...

What is the virus, and where did it come from?

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The virus actually started out as a Vought-funded project, with the company hiring gifted scientist Dr. Edison Cardosa (Marco Pigossi) to create a bioweapon that could subdue and control Supes. To enable Cardosa to work without outside interference, Vought created The Woods, an underground medical facility, much like the one Homelander revisited in episode 4, for he and his partner Richard Brinkerhoff (Clancy Brown).

Over time, though, the whole operation was co-opted by Godolkin University dean Indira Shetty (Shelley Conn). Many of the Supes illegally experimented on in the lab were students, including brothers Luke and Sam Riordan.

Unsatisfied with the idea of merely controlling Supes, Shetty pushed an increasingly uncomfortable Cardosa to make the effects of the virus more and more devastating and, eventually, ordered him to make it airborne. While he refused to do the latter, he succeeded in making it lethal, and transmittable through bodily fluids.

Turns out, Shetty's husband Paul and their young daughter Lily were killed in the Crash of Transoceanic Flight 37, the rescue mission Homelander (Antony Starr) botched in The Boys season 1. After the plane was hijacked by terrorists, he and Queen Maeve (Dominique McElligott) were tasked with saving the day, but Homelander carelessly ended up destroying the pilot's control panel.

With the plane going down, Maeve suggested Homelander fly its passengers to safety, but he refused, complaining that it'd take him 123 trips. Eventually, the two Supes flew down on their own, leaving everyone on board to die – and setting Shetty on a grief-stricken quest for revenge against all Supe kind.

In the penultimate episode of Gen V season 1, Shetty was killed by mind-controlling Supe Cate (Maddie Phillips) after the latter forced her to reveal the truth about The Woods and its creator, Thomas Godolkin, as well as her own personal motivation for creating the virus.

How does Victoria Neuman have the virus?

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Disturbed by Shetty's vision for the virus, and haunted by the part he played in making it, a guilt-ridden Cardosa makes plans to start a new life for himself and his family in Gen V season 1 episode 7. But things take a tragic turn after he decides to hand over the last remaining sample of the virus to Neuman, who he believes is a straight-up, do-gooder politician. Albeit one with anti-Supe attitudes...

The pair meet in a secluded parking garage, where he asks her to assure him she's aligned with Vought's original plan for the virus: to use a non-deadly version of it to control Supes or, at their request, rid them of their powers. She agrees.

Luring him into a false sense of security, Neuman vows to protect him and his family if news of the substance were to ever go public and goes to give him her card. As she does so, she asks him whether the sample he's brought is the only batch in existence and if there's anyone else in the world who can replicate it, to which Cardosa replies that there isn't. She tells him he's a hero, to which he smiles shyly.

With that, he looks down at the card, and realizes it's completely blank as a drop of blood drips from his nose onto it. He apologizes, blaming the dry air, but when he looks up at Neuman, he sees her eyes are glassed over. Neuman then uses her powers to explode his head.

Part of said scene was glimpsed in the "previously on" section of this week's episode of The Boys.

Now, it looks like Neuman has enlisted the help of her long-term partner Sameer (Omid Abtahi) to make the virus suitable for what she's planning to do with it. Which brings us onto the next section...

What does Neuman want to do with the virus?

((Image credit: Prime Video))

At this stage, it's kind of unclear what Neuman's true intentions with the Supe-killing virus are, especially when you consider that it's kind of contagious and she's a Supe herself, but The Boys' latest installment offers up a hint as to what she's planning.

"You turned my farm into an infectious disease lab", her adopted father Stan Edgar (Giancarlo Esposito) says, as they escort Butcher (Karl Urban and the rest of his gang around the premises. "I can only assume that you're searching for a way to control Homelander?"

"He's a Freudian cesspool; random impulse and deep insecurity. There's no one that can control that. You're putting yourself and Zoe in terrible danger," he goes on, before she snaps back: "No! You put me and Zoe in terrible danger. You used me like you use everybody else. Somebody had to protect her."

"You took a bright-eyed little girl and turned her into a..." Edgar replies, before an angry Neuman cuts him off: "Into a what? A monster? Is that why you had me hide what I was? Stick to the shadows, never reach too high? You were ashamed of me. My daughter will never have to live like that."

In a follow-up scene, MM (Laz Alonso) asks Butcher what he has planned for the virus, to which the foul-mouthed Brit spells out: "Starlight blinds the b**** and before she knows what's what, I'll stab her with a dose."

The Boys season 4 is currently streaming on Prime Video, with new episodes dropping every Thursday. For more, check out our latest coverage on the show: