The top 10 ‘Mare of Easttown' murder suspects

Kate Winslet Mare of Easttown
(Image credit: HBO)

This post contains detailed spoilers for Mare of Easttown.

Part of the crime drama thrill is playing armchair detective, and HBO’s Mare of Easttown is proving to be a Sunday night whodunnit with enough suspects to suggest multiple theories. At the start of the seven-episode series, Detective Mare Sheehan (Kate Winslet) was facing criticism from the small Pennsylvanian town for the lack of results looking into Katie Bailey’s (Caitlin Houlahan) disappearance. This introduction to Easttown ended with the discovery of Erin McMenamin’s (Cailee Spaeney) body, which gave Mare a new case to solve with potential links to the other mystery plaguing her department. In this week’s explosive “Illusions,” the identity of Katie’s abductor was revealed — he had also recently attacked and grabbed another woman — and this initial connection is now unlikely. 

When Katie explains the parameters of her imprisonment to Missy (Sasha Frolova) it becomes clear that his choice of sex worker victims is random, whereas the Erin murder doesn’t read like a kidnapping gone wrong. The latter is underscored when Mare and Detective Colin Zabel (Evan Peters) interview another young woman who escaped an attack by a man who turned out to be Wayne Potts (Jeb Kreager). A partial license plate and vehicle description led to seven potential leads, which ended in tragedy for Colin Zabel and the rescue of Katie and Missy. Colin was shot in the face by Wayne and the gunless Mare — she is still suspended — was injured in the melee — her injury is not fatal. Someone still has to solve Erin’s murder and unfortunately, the sweet and heroic Zabel decided now was the time to grab life by the horns. A spontaneous smooch with Mare is all she is left with and RIP to this short-lived relationship. This pretty much confirms that Colin is not Erin’s killer, and while his death is upsetting, it also puts those worries to bed. During the flirtation and drunken confessions, I was concerned his arrival was no coincidence, and that the perpetrator was under Mare’s nose the whole time. Director Craig Zobel has said that the person behind Erin’s death will not be someone “out of left field” so that answer is still in close proximity to Mare. 

With two episodes left to go, here are the suspects in order of who we think Erin’s killer might be (starting with the least likely), and the identity of the killer could be the same answer as the father to Erin’s baby, DJ. So far, we know that ex-boyfriend Dylan (Jack Mulhern) and her teacher Frank Sheehan (David Denman) are not the baby daddy, but the paternity is a pertinent line of inquiry.

A bit of a brief update! Mare of Easttown gave us some answers in their penultimate episode. Or did they? Check out all of the questions we have now that the series has "revealed" its killer

10. Siobhan Sheehan (Angourie Rice)

Could it be someone living under Mare’s roof? Siobhan was one of the last people to see Erin alive but acted with kindness and she really doesn’t have a motive. Any early suspicion has been pretty much erased but never say never.  

9. Brianna Delrasso (Mackensie Lansing)

One of the first people questioned, Brianna definitely beat the crap out of Erin but she is no longer a prime suspect. Her rage was visceral but humiliation, not a permanent end was her motivation. She has gone from a DGAF to losing that hardened exterior as she offers boyfriend Dylan a shoulder to lean on, while also questioning why he was missing when she woke up the night of the killing.  

8. Richard Ryan (Guy Pearce) 

Mare opted to go on the Saturday night date with Colin instead of Richard, and while I think Richard can’t be trusted when it comes to his motives for getting close to Mare, I also don’t believe he is Erin's murderer. First of all, he has an iron-clad alibi — he was hooking up with Mare — and second, he appears to have no connection to this town. Rather, after more than two decades without another literary hit, I think the author is hoping to find inspiration from Easttown and Mare as a means to a book prize end.

7. Deacon Mark Burton (James McArdle)

Another gag in the SNL sketch is the Deacon clearly did it and it is no surprise the Catholic priest is under suspicion after the lies he has told to Mare regarding the night Erin was killed. His transfer to this parish occurred after a 14-year-old girl alleged he assaulted her and he was close enough to Erin for her to call him when she was upset. If we are to believe what he tells Mare’s cousin Father Dan Hasting (Neal Huff) in “Illusions” — for the record, I do — he picked her up at the woods and drove her to Brandywine Park after she received a text that made her “hysterical.” Fear that he would be accused (thanks to his reputation) led him to dump her bike in the river, which was incredibly stupid but doesn’t make him a killer. I also don’t think the Deacon was “with” Erin in the Biblical sense and he is at least innocent in this case.  

6. “Ferret Man”  

The first crime Mare was called in to investigate in Episode One was a Peeping Tom who Mrs. Betty Carroll (Phyllis Somerville) reported as having frightened her granddaughter. Mare considers this whole prowler endeavor to be a waste of time but still went so far as chasing a would-be suspect (it was actually an old confused man looking for his home). This might be a massive red herring but the way this figure (and the creepy sketch) keeps peppering the conversation suggests this animal resembling figure is more significant than Mare first believed. Alas, Betty died from a heart attack (and the actress sadly passed away last summer) so she will never find out how useful her tipoff was.   

5. Jess Riley (Ruby Cruz)

Erin’s BFF has been slow to tell Mare important details in a bid to protect her friend. Or so we thought. Teaming up with Dylan to find the diaries suggest her loyalty is more ambiguous, although there is nothing to indicate that she was also at the park when Erin was murdered. She did slip an unseen photo from the pages of Erin’s diary before burning it. Suffice to say, Jess is now also aware of the paternity identity. Is she in danger now that she knows? Or is she protecting this man rather than her friend? 

4. Dylan Hinchey (Jack Mulhern)

The ex-boyfriend is an obvious suspect and Erin’s father also thought Dylan had killed his daughter. He took swift revenge in the second episode and shot to kill — but was unsuccessful in this endeavor. His alibi is Brianna, but we found out this week that she lied about his whereabouts. His animosity toward Erin could have led to calling her to the park under the pretense of discussing their son’s operation. In “Illusions” he steals Erin’s diaries from the secret hiding place (along with the money she had saved for DJ) and sets fire to the evidence. What is in those pages is so damning? Could the person who seemed the most guilty from the off be the killer? 

3. Billy Ross (Robbie Tann)

So most of the Ross family are top of my list and relevant information about Erin living with her dad’s cousin (her second cousin) for a few months was revealed in “Illusions.” This was about three years ago and was during the time when Kenny became violent after Erin’s mother died from leukemia. It wouldn’t seem like an odd occurrence for a relative to reach out like this but our (and Mare’s) suspicion is raised by how evasive he is about the details while also downplaying how long she stayed there. He makes his excuses and leaves, but Mare can’t help eyeballing his abandoned beer bottle and the DNA secret it might contain. This is definitely a motive for murder and the potential paternity solution in one.

MORE: Will there be Mare of Easttown Season 2?

2. Ryan Ross (Cameron Mann)

One of the silliest moments in the other recent HBO whodunnit The Undoing was when the murder suspect Jonathan Fraser’s (Hugh Grant) teen son ran the murder weapon through the dishwasher (twice). Perhaps this is another case of a child trying to protect his father, but maybe Ryan took the opportunity to confront his father’s girlfriend while everyone was out at Frank’s engagement party. Where Ryan (who is probably pushing 13 at the most) found a gun or even got to and from the park is unclear, but there is definitely some pent-up rage lingering as his use of a cafeteria tray as a weapon against his sister’s bully highlights. The themes of this series are also exploring how the sins of parents impact their children and this would be a pretty stark portrayal of this sentiment.  

1. John Ross (Joe Tippett)

The whole Ross clan has been acting shifty since the second episode, and while John is the husband of Mare’s bestie Lori (Julianne Nicholson), his recent activity puts him directly into the super suspicious crosshairs. When Mare told Kenny (Patrick Murney) that his daughter had been killed, she took Kenny’s cousins John and Billy (Robbie Tann) along for support. John seemed like a supportive relative and friend but also looked uncomfortable, which at the time read as sorrow. Since then, he has provided an alibi for Mare’s ex-husband Frank — yes, SNL was right when they said everyone is related — to who he claims he gave a ride home at the time of the murder. Frank was blackout drunk and can’t remember, which is super convenient for John. What is his motive? Perhaps, he is the father of Erin’s baby and the woman he has been having an affair with until recently was Erin.   

Emma Fraser

Emma Fraser spends most of her time writing about TV, fashion, and costume design; Dana Scully is the reason she loves a pantsuit. Words can also be found at Vulture, Elle, Primetimer, Collider, Little White Lies, Observer, and Girls on Tops. Emma has a Master’s in Film and Television, started a (defunct) blog that mainly focused on Mad Men in 2010, and has been getting paid to write about TV since 2015. It goes back way further as she got her big start making observations in her diary about My So-Called Life’s Angela Chase (and her style) at 14.