Who killed Erin in Mare of Easttown

Ending Explained

By Meghan O'Keefe

May 30, 2021 // 11:07pm

Mare of Easttown Episode 7 “Sacrament” finally reveals who killed Erin McMenamin (Cailee Spaeny)…after one last feint. While last week’s episode of the HBO show ended with Mare Sheehan (Kate Winslet) racing to confront Billy Ross (Robbie Tann), whom she thought was the killer, it also left us of the cliffhanger question of what was in the photo that Jess (Ruby Cruz) showed Chief Carter (John Douglas Thompson). The Mare of Easttown finale opens with that reveal and the twist that it was John Ross (Joe Tippett) who was having the incestuous affair with Erin. And that John was asking Billy to take the fall to protect his family.

Mare is able to apprehend both John and Billy right before John tried to kill his brother. It seems that Erin McMenamin’s murder has been solved. John Ross is able to explain everything that happened that night, except an important detail about the murder weapon, which Mare initially shrugs off because John claims he simply doesn’t remember. It’s not until about 35 minutes into the Mare of Easttown finale that Mare realizes who really had the murder weapon on the night Erin was killed. And it wasn’t John Ross, but his 13-year-old son, Ryan (Cameron Mann).

Yup, Ryan Ross killed Erin McMenamin and the whole Ross family was at some point in on the coverup. Ryan found messages from Erin on John’s phone asking him to meet her at Brandywine Park. Incensed that Erin might tear their family apart, Ryan responded to her messages. He then rode his bike to the Carroll house. There, using the keys to the shed he had (thanks to the fact that he mowed their lawn), he stole Mr. Carroll’s ceremonial gun. He rode his bike to Brandywine Park and waited for Erin. Ryan later tells Mare he only intended to scare Erin, but the older cousin tried to wrestle the gun away from him. He shot her in the hand in the scuffle and, as she turned to face him, he shot her in the head by accident.

A shell-shocked Ryan called his father John for help. He picked up the boy and told him that he and Billy would take care of it. That is why Billy was spotted cleaning bloody clothes. It’s why Ryan had the violent outburst at school, fixated on the news story about missing girls, and kept a certain “secret” with his father. Lori (Julianne Nicholson) was finally told the morning Mare visited to ask about Billy Ross. Lori took John’s advice and lied to Mare about Billy being the killer. The couple might have successfully framed Billy for their son’s misdeed had Mare not stumbled upon the brothers in the woods. John then took the fall for his son. Lori kept quiet, later revealing she would have taken the secret to her grave. But Mare figured it out and ruined everything for her best friend.

“It was so heartbreaking,” Mare of Easttown star Julianne Nicholson told Decider about the reveal. Kate Winslet had asked her long-time friend to come on board and play Lori without revealing what the character would go through in Episode 7. Nicholson only received the first six scripts before signing on and then after she was confirmed for the part, finally learned the devastating truth.

“I mean, like the audience, I sort of thought I knew who did it in every episode, and then it was sort of revealed that I was wrong. I thought it was maybe Lori, but I think that Ryan doing it is actually the saddest outcome,” Nicholson said.

Of course Mare of Easttown‘s insane finale only came together like it did thanks to the genius of writer and creator Brad Ingelsby. The Philly-area native drew upon his own life experiences to create the hyper-specific series. Decider caught up with Inglesby this week to talk about how he decided Ryan Ross killed Erin McMenamin, what Dylan Hinchey (Jack Mulhern) was really up to on the night of the murder, and which fan theory shocked him the most.

And if your most pressing question after the finale is “Does Mare kill herself at the end of Mare of Easttown?”, Ingelsby clears that final shot up for us, too.

Here, in creator Brad Ingelsby’s own words, is the Mare of Easttown ending explained…

DECIDER: I know that you have said in other interviews that you had the ending in mind before you started writing, but how early in the process did you know Ryan would be the killer, and what point did you know it had to be him and why?

BRAD INGELSBY: So I had the character of Mare, and then I spent probably eight months with the other character and trying to craft the ensemble… But then I didn’t really start writing because I didn’t know where it would go. And I knew that we had to have a good ending that had to be emotional and surprising. And so it just hit me one day. I was like, “Oh, what would be the hardest journey that Mare would have to go on in the show?” And then it became clear. “Oh, it has to go through Lori, the best friend; it’s the devastation of her son.” And it just felt like in terms of themes of the show — Mare losing a child and Lori losing a child and mercy — it felt like, wow, that would be really potent emotionally if it had to be Lori’s child. Because Lori had been by Mare and by her side and now Mare has to reciprocate in a way that’s challenging. So it took a little while to land on that but I wouldn’t start writing until I knew where it was ending because I knew it was going to be challenging to craft all the surprises along the way.

I hope it works emotionally. That’s my biggest takeaway.

Another question about the ending: In the closing shot you have Mare going up into the attic. For me, I took it as a moment of personal catharsis. She finally has the wherewithal to face where her son died. My only concern is other viewers might think she herself is committing suicide. Were you worried about that? Can you just make it clear what’s going on?

It’s a really cathartic moment. It’s definitely a moment of hope. Like we definitely…it was in the edit, we were like, “Is anyone going to think Mare is…?” It was definitely on our minds, but we experimented with a couple music choices and we felt like that one was hopeful enough that we were confident an audience would go, “Oh, this is her going to confront the thing that’s been haunting her.” And so we one hundred percent wanted it to be a moment of hope at the end, that leaves you thinking Mare is going to be okay.

Yeah, I just wanted to confirm that because not everyone…

Yeah, I know, I know. And I’m hopeful it doesn’t ruin it. We wanted it to be a moment of hope at the end, you know?

I know that the show is obviously an original story created by you. It’s not based on a book, but a lot of people thought or assumed it was based on a book. I don’t know if that’s because IP drives what gets greenlit or because it just speaks to how novelistic the whole world just feels. Can you talk about making the show feel so dense and lived in first, and then second, what was it like pitching this to HBO? Because obviously a lot of their limited series are based on books. Was it a struggle to get an original concept in?

To answer the original question, I think the “lived in” quality, it was helpful that I grew up there and was just able to add the level of detail. The show is about a certain part of the country, a certain group of people. And how specific we can be with how they live and what they drink and what they eat and what they wear, the better. In the specific is the universal, right? So that was important to me and luckily that just came from having grown up there. I’ve been in those homes and on these streets, and I’ve seen the interior lives of these characters. That was coming from a place of experience.

Then, so I think in terms of HBO and selling it, we had Kate [Winslet]. We had sent Kate two scripts and Kate had signed on. So going to HBO with Kate Winslet made it a lot more appealing because everyone wants to work with Kate. She’s so incredible. So I think having a great actress like Kate who had raised her hand. And I think at that point we had a couple more scripts so we were able to show them an even deeper dive into where the story was going. So I think it was a combination of having a few scripts to really show them the execution of it and then also having Kate Winslet say, “I’m willing to do this.” That was the biggest piece.

I want to circle back, not to the finale, but to the most shocking moment of the season so far which was when Colin Zabel was killed. I talked to [director] Craig [Zobel] about it before the show came out. Can you talk about what inspired that choice, storytelling-wise? Because it felt like a Game of Thrones-style mid-season death. And also building Colin to be this lovely, empathetic millennial version of a detective, which I hadn’t seen before.

Yeah, you know we had this idea of Zabel. He was always going to die there. That was always in the script. We had this idea with Zabel that he was an imposter. He’s a hero detective, but just like everyone in the show has a secret about them, in the case of Zabel, his secret is “I didn’t really do this thing. I am an imposter. I’m acting as if I’m this great detective when really I’m not.” And I think what made it so heartbreaking is he finally arrives at this place at the bridge scene where he’s finally ready to confess to Mare the truth and also begin to take ownership of his life in a way. Like he says, “Oh how do you know what I want?” And we get the sense that he’s willing to turn a corner in his life. He’s going to move ahead in a much more concerted way… and then he gets killed.

I think what was hard about it was Evan…and I remember saying this to the editors early on: “Evan is so charming in this show, we’re in trouble because the audience is going to love him so much.” Whereas on the page, he was charming enough, but Evan took it to a whole other level where we were like, “Oh, this could be a problem.” Evan was just so good that suddenly this is really going to be a shock and maybe not in a good way because the audience has become so attached to him.

The only loose end to me was, and not really a loose end, but just to confirm…Dylan. What was he doing out at 2 AM? Was he really driving around? Why did he burn the journals? Pulling a gun on Jess seemed extreme. Is it true? Did he really want to keep the baby that badly?

It is. And we grappled with the gun part a lot. I’m glad you brought that up. Because we were like, “Is this going to feel too much in that moment?” Like he did want to keep the baby and that was intention all along so that is the answer there. And we struggled with how to make it dramatic. Do we give him a gun? There was definitely a version where he didn’t have the gun, but then it deflated it in such a way. It was almost too tame. So we felt like he had to have a gun to threaten her.

But as to where he was that night? I think we always just said, “Yeah, he actually just went out to smoke some weed and he drove around in his car and that’s actually where he was.” And his parents wanted to keep the baby. He wanted them to keep the baby. And he was willing to do these things to have them keep the baby and that was where his arc was going to end. I think we did have one other scene in the finale just to put him in a better place.

Was it the scene where he brought the money for D.J.’s ear surgery to Lori? That felt like it confirmed that he was sincerely trying to take care of the baby.

Exactly. It was one nice note. Dylan does a lot of terrible things in this show, we had to give him an ending beat of grace.

I like watching this show for the family drama, but covering this show, I’ve seen a lot of crazy theories. Have you been aware of these theories, of who the killer might be? And do you have a favorite one that amused you the most?

That’s really funny because it has been the part of the show – I’m glad you said the family drama — because I’ve been so surprised by the theories. I always saw this as a family drama that had a mystery element to it. I’ve been shocked by how into the Whodunnit? people have gotten. Now I’m incredibly lucky and grateful that it has. It’s kept them around and it’s kept the viewers there.

But I think the one that surprised me [the most] that I’ve gotten consistently from people is Siobhan (Angourie Rice). Like we were not even actively trying to make her a suspect at any point in the show. Other people I could point to moments where we were like really trying to have the audience lean in or linger, but I’ve gotten a lot of people telling me Siobhan. And that’s the one where I’m like, “No, her journey is ‘I gotta get out of town.’” It was always about this person who’s tried to keep the family together, but they have to fly away at the end. That was always going to be her arc in the show. So that one’s the most surprising to me.

Obviously you’re from the Delco area. What has been the reaction of your friends and family to the show’s success and how it’s depicting the world they grew up in?

Yeah, it’s been really positive. I think they’re just excited to have people talking about Wawa. I think they’ve gotten a kick out of the show itself and I think they’re happy that their way of life and that their community is getting a moment in the spotlight. I tried to have it be an honest representation of the place. And also a very loving representation of the place. I hope that comes across and it’s not condescending in any way. We always tried to make each of the characters human and dimensional. That was really important and I hope we’ve achieved that in the show.

One other character I wanted to ask about. Richard (Guy Pearce) flits in and out of the finale. He and Mare come back together and then he leaves for a year. Is there a reason why you had him leave before the end of the finale and not tie a bow on that relationship?

You know what it was? It was always in the script, but Kate really drove it home. She felt strongly that if Mare was in such a good spot in her life, it was going to be too easy when Mare went to see Lori. Like, “Everything is going so great in my life. I have Drew. I’m in this loving relationship with this man nearby…” And we just didn’t want it to be that. That Mare’s life was so perfect now and that it would be easy for her to make the decision to go over to Lori’s house.

So we always wanted it to be a relationship where he came into her life at a very specific moment in time. He provided some tenderness and light in her life and he helped get her through this time, and then he left. And you know it’s true to life in a lot of ways that you have these relationships with people who come into your life and then they leave. But then you look back at that time…I have friends like this. Like I don’t talk to them that much now, but man, I’m so glad that I had them. And that’s what Richard was always going to do in Mare’s life in this time of the series.

Before I go, Jean Smart… I adore her. Did you guys have to walk her through playing those video games on the tablet or did she just already know? What was the process behind getting Helen Fahey to be the super destroyer gamer?

That idea just came from my mother-in-law, whom I love, but every time I look around the house, every time she comes to visit, she’s on her iPad. I think her game was something different. I think she was still doing Words with Friends. I just loved that idea and wanted to bring it in. But then we thought, “Words with Friends isn’t all that humorous. Let’s have her play something that a kid would play.” And so we got the rights to Fruit Ninja, but I don’t remember teaching Jean to do it. So maybe she just had a talent that we didn’t know about. She was very into it. She’s very good at it. So you’ll have to ask Jean if she played it before because she seemed to pick it up quickly.

(This interview has been edited and condensed for clarity.)

Where to stream Mare of Easttown

• Ending Explained
• HBO Max
• Kate Winslet
• Mare of Easttown