It only took eight episodes and a whole lot of rage, but we finally have answers to the question at the heart of Furious Season 1: Who killed Isabel and why?

If you tuned into the Hulu hit at the beginning of the series just for Emmy Rossum or Lola Petticrew (we hope not Jake Lacy otherwise your heart may now be broken at how treacherous his character is) you may have found yourself enamored with the story at the center of the show.

Inside the overarching tale about rage and societal misdoings is a mystery about what happened to one young girl and how it happened. We finally have resolution and an explanation from series creator Liz Meriwether. Keep reading for the full breakdown.

**Spoilers ahead for the entire first season of Furious, now streaming on Hulu**

Furious Ending Explained: Who Killed Isabel and Why?

In the end, it was not Jay Easton (Peter McRobbie) or his daughter, Emma Easton (Hope Davis), who killed a young Isabel (Larissa Campos), but rather Catherine (Petticrew) herself, who took her best friend’s life out as an act of mercy. While never explicitly stated, Catherine appears to have experienced a bout of dissociative amnesia, a mental condition that causes fugue as the body and mind’s response to experiencing a traumatic experience.

In the finale, as Catherine storms the Easton property in Connecticut to find out what really happened to her young best friend, the audience learns that during their joint visit to Jay Easton and his friends as young girls, Isabel began to hemmorage as a complication from childbirth. This occurred after Jay sexually abused her and left her to bleed out in his panic room. Emma Easton ultimately was the one to fetch Catherine and bring her to Isabel, who asked her to take the needle full of heroin on a nearby table and inject her with it. Catherine tearfully obliged as her friend complained of being in pain everywhere and not wanting to hurt anymore.

In her final moments, Isabel tightly squeezed Catherine’s hands, which left both a physical and mental imprint on the show’s vengence-seeking character, as earlier in the season Catherine explained that she does not have feeling in her hands and could not remember why. As Emma Easton flees the room after being held at gunpoint by Catherine, Alice (Rossum) holds Catherine’s hands and comforts her before placing her handcuffs and officially placing her under arrest.

After Catherine is taken away on a stretcher — earlier in the evening, Emma Easton shot her in the greenhouse — Alice sneaks off to Jay Easton’s bedroom and kills him, only making the decision to take his life after he calls her “the movie star,” referencing the video taken of her as a child. In that moment, Alice steps on Jay’s oxegyn chord and closes his mouth and nose as he goes into respiratory distress. This truth is only outed after Alice visits Catherine in prison and reveals that she knows what Alice did.

The season ends with Alice watching the video of herself as a teenager, crying, and then pulling up a list of all the known accounts that have downloaded the video, teasing a journey of vengeance in Season 2 for Rossum’s character.

Furious Creator Liz Meriwether Explains the Choice To Have Catherine Be Responsible for Isabel’s Death

While many showrunners and series creators know exactly where they are taking a story at the outset, Meriwether told DECIDER in a preseason interview that she and her writing team only stumbled onto the idea of having Catherine be the one who actually injected Isabel after writing the first two episodes.

“It came out in the writer’s room, this idea of memory, her piecing together the memories that she had of what happened to her. So in a way, it’s not a whodunit, it’s the story of a serial killer trying to figure out why she’s killing so many people. It’s a serial kill trying to figure out why she’s a serial killer, which I think is really interesting,” Meriwether explained. “I knew that I needed a mystery, I knew I needed some kind of thing that’s pulling you through. We know who the killer is in from the first moments of the show i think I felt like there there needed to still be something with a lot of secrets that needed to come out.”

For Meriwether, the option to not plot out the ending at the very beginning is also freeing, in a way, as it gave the team the room to take the story where it really needed to go.

“Coming from comedy, I’m a little bit more comfortable with sort of finding it. I think I don’t actually, a lot of the time, know where I’m going to go. But it does help keep it alive and it sometimes can lead to a fair amount of backtracking and having to kind of rework. But I didn’t know where that was going, but it came from a place of thinking about trauma, thinking about what was going on for Catherine,” she said.

What Does the Furious Season 1 Finale Mean For Furious Season 2?

Thankfully, Hulu has already renewed the series for a second season and it sounds like Rossum — who also serves as executive producer on the project — and Meriwether have a good idea of where they can go with the story in Season 2.

While Meriwether says she sees it as a continuation and another opportunity to explore a big case like the one from Season 1, Rossum is more interested in the internal changes for her characters and what lies ahead after Alice has permanently changed her values following the murder of Jay.

“I think Alice and Catherine are people who have been underestimated and are both feeling somewhat powerless, even though they’re on these missions for justice and vengeance. And when Catherine later on says that killing someone is power, it’s taking power back, I think that that changes something in the way that Alice thinks about what Catherine is doing,” Rossum explained.

Furious Season 1 is now streaming on Hulu. The series has been renewed for a second season.

If you’re new to Hulu, the basic (with ads) price is $11.99/month. If you want to upgrade to Hulu ad-free, it costs $18.99/month.

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