Did you read The Sanatorium by Sarah Pearse and have ALL the questions about the ending? And what’s with that epilogue – who is following Elin around the Sanatorium? Come check out my spoilers and plot summary for The Sanatorium and then let’s discuss this baffling case of multiple murders in a Swiss alps resort and the equally baffling ending! Check out this Spoilers and Plot Summary for the Sanatorium!

The Sanatorium by Sarah Pearse. Published February 2, 2021 by Pamela Dornan Books.
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The plot summary below will contain spoilers. If you want to read my spoiler free review of The Sanatorium, you can find it here.
TABLE OF CONTENTS FOR THE SPOILERS AND PLOT SUMMARY FOR THE SANATORIUM
- Plot Summary for the Sanatorium
- Who was the killer in the Sanatorium?
- WHAT WAS THAT FINAL CHAPTER? The Sanatorium ending, explained — or at least the possibilities explored!
- BREAKING NEWS: Yes, there will be a sequel to The Sanatorium. Elin will be back! Will we find out who’s is stalking her? Maybe not…
Spoilers and Plot Summary for the Sanatorium by Sarah Pearce
Elin and Will arrive at Le Sommet, a resort in the Swiss Alps. She’s a British police officer and they are meeting her brother, Isaac, and his partner Laure. Elin and Laure knew each other growing up, and now Laure is the assistant manager at Le Sommet and she and Isaac are engaged.

Adele, a hotel cleaner at Le Sommet, finds a copper bracelet outside one of the rooms. When she leaves work she is attacked by someone in a gas mask.
Isaac and Laure show Elin and Will around the hotel. They point out Lucas Carron, the hotel owner and his sister Cecile, who helps manage the resort. They mention that the hotel’s architect, Daniel, was a friend of the Carron siblings who disappeared while the hotel was being planned.
The next morning Isaac says he can’t find Laure. Then a skiier discovers the body of Daniel, the missing architect.
Elin talks to Isaac about where Laure could be.
Elin also tells her brother about a case that is preoccupying her: the murder of two teenage girls. An anonymous tip led the police to a suspect: Mark Hayler. Elin went to question him and he ran. She chased him along the beach and into the surf and he hit her with a rock and got away. After that, she took a leave from work.
Elin sees what she thinks is blood on the rug in Isaac and Laure’s room, but Isaac says Laure cut herself shaving.
Elin seems slightly suspicious that Isaac has something to do with Laure’s disappearance. She tells Will that she thinks Isaac might have killed their brother Sam, who drowned when Sam was eight, Elin was twelve, and Isaac was ten.
Sam’s death was ruled an accident, but Elin has had flashbacks about seeing Isaac with blood on his hands.
This plot point will be important later:
Will convinces Elin to try to relax at the spa. As Elin leaves the pool area alone, someone pushes her from behind into a freezing outdoor plunge pool. Flashing back to Sam’s death, she panics but manages to climb out. Will tells her she must have slipped.

The resort is evacuated due to the storm and avalanche risk. Isaac refuses to leave as Laure is still missing. Adele is found dead in the pool.
Due to a small avalanche blocking the road, the police can’t come, so Elin secures the scene and collects evidence on their behalf.
People tell Elin that Laure and Cecile seemed at odds. Lucas confesses that he and Laure had a short fling and that he had been receiving anonymous, threatening notes.
Someone wiped much of the resort’s CCTV footage, but there is footage showing that Laure was following Elin at the spa. She wonders if Laure is the one who pushed her and is also the killer of Adele and Daniel. Files from Laure’s computer reveal that Laure was providing information to a journalist on an expose on the resort.

Laure texts Elin asking to meet. Instead, Elin finds Laure’s body. They also find a flash drive and a copper bracelet at the scene. The hotel CCTV cameras are down and the weather is still too bad for the police to get to them. Elin thinks Lucas and Cecile are acting strangely.
Elin connects numbers engraved on the copper bracelets to some old medical files on the flash drive.
Another hotel employee, Margot, goes missing. Elin tracks her phone within the hotel and she and Will go looking for her. Margot escapes and Will gets stabbed.
Isaac and Elin discuss Sam’s death. Isaac says it was an accident and that Elin was the one with him at the time. Elin finally remembers the details of her brother’s death and in doing so recalls that Margot dropped something when she was struggling with Will.
She finds what Margot dropped – an envelope with old medical records and gruesome old photos of medical experiments on women. One entry has the same number as the copper bracelet. Elin suggests that Margot was avenging the deaths of five relatives who were sanatorium patients in the 1920s.

Elin finds a secret tunnel. She and Lucas go to investigate and find the killer’s lair. Margot is there, injured and dying. She turns to Lucas to say that Margot was working with someone else, but Lucas has disappeared.
Elin goes to Cecile for help and they search Lucas’s office for clues. Cecile confesses that Daniel’s body was actually found in the hotel but that Lucas dumped it so as not to get bad publicity.
SPOILERS: Who was the killer in the Sanatorium?
After talking to Ceclie, Elin realizes who the killer is. She rushes to the pool area where she finds Lucas, injured.
The killer is … CECILE. When Cecile was sixteen, Daniel raped her. Lucas knew and did nothing. The rape destroyed Cecile’s life. She became pregnant as a result. Terminating that pregnancy left her unable to have children.
Margot contacted Lucas and Cecile about her relatives who had been treated and abused at the clinic in the 1920s. Lucas buried the information as it would have been bad publicity for the resort.
Cecile then killed Adele because Adele helped Lucas cover up Daniel’s murder.
Cecile enlisted Margot’s help in murdering Laure. She killed Laure because Laure found out what Cecile was doing and threatened to expose her.
Cecile wanted to get caught for Daniel’s murder so she could “tell her story.”
Cecile and Lucas struggle and fall in the pool. Elin watches, terrified and thinking about the day her brother died. But she jumps in and saves Lucas. The police arrest Cecile and Lucas.
Do you think Cecile’s motivation for killing Laure and Adele made sense?
I can accept that Cecile waited years and years to get her revenge. She killed Daniel, who raped her. But then she killed Adele because Adele helped Lucas hide Daniel’s body, which meant that Cecile got away with murder. She wanted to get caught to get her story out.
Then she killed Laure, and then was going to kill Lucas, and I guess Elin would have been next? I don’t know – it was all a bit farfetched for me. Personally, I liked Margot as the killer a lot better. I guess she was helping Cecile, but still.
What WAS that final chapter of The Sanatorium? The Sanatorium Ending Explained (or not!)
In the epilogue of The Sanatorium, Elin and Will finally leave the hotel but as they board the funicular, someone follows them, someone who admits HE (or she?) was the one who pushed Elin into the plunge pool.

Was it Isaac, Elin’s brother, meaning he was the one who killed Sam?
Was it Hayler, the guy from Elin’s case back home? Is he now going to kill Elin? WTF?
Or was it someone else following her? (Be sure to check out the comments and decide if you are Team Isaac or Team Hayler or Team Someone Else. What do you think?
Yes! Elin is BACK in a sequel to The Sanatorium
So some of us in comments thought that, given that weird last chapter, there had to be a next book.
Good news: we may just find out who was following Elin.
Bad news: if you didn’t like Elin before (and there are a lot of people in comments who didn’t) she’s back in the next book.
Here’s the synopsis of The Retreat.
An eco-wellness retreat has opened on an island off the English coast, promising rest and relaxation—but the island itself, known locally as Reaper’s Rock, has a dark past. Once the playground of a serial killer, it’s rumored to be cursed.
Detective Elin Warner is called to the retreat when a young woman’s body is found on the rocks below the yoga pavilion in what seems to be a tragic fall. But the victim wasn’t a guest—she wasn’t meant to be on the island at all.
When a guest drowns in a diving incident the following day, Elin starts to suspect that there’s nothing accidental about these deaths. But why would someone target the guests, and who else is in danger? Elin must find the killer—before the island’s history starts to repeat itself.
Sounds familiar, right? Luxury resort with a dark past and Elin on the case! Elin does seem to find a lot of bodies in expensive wellness retreats.
Here is my Review of the Retreat and when you’ve read it (or if you don’t want to read it and just want ALL the spoilers) come over to my Spoiler Discussion for the Retreat!
Insights About Elin From Sarah Pearse
Also I recently listened to a podcast featuring Sarah Pearse, and I am here to say she seems LOVELY. I would love to have a cup of tea with her!
Here are some insights for those of you who aren’t fans of Elin (she didn’t bother me nearly as much as she did some of you lol. But I do get where you are coming from and so does Sarah!)
Sarah said she didn’t want the book to be a police procedural. She wanted Elin to be a “normal” person. (She is a police officer, but I she’s guess off-duty and out of her element in a different country.)
Sarah also seems aware that Elin is “somewhat controversial” and “perhaps a little intense” and I loved that she didn’t get defensive about it. A lot of authors would have been offended.
In the podcast, Sarah had some interesting thoughts about how female detectives in police procedurals get pigeonholed into a very masculine sort of characterization and wanted to try to work against that.
She also hinted that in book two Elin will have to reckon with her own memory and how reliable it is. IS ELIN SAM’S KILLER? Will she have to arrest herself? Anything seems possible!
Talk to me in comments! What were your thoughts about this one? That did you think about the ending of the sanatorium? I have seen varied opinions! And be sure subscribe to comment replies – you can subscribe to all comment replies or just to the replies on your individual comment.
Join the Spoiler Discussion for the Sanatorium!
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I couldn’t finish the book. At first I was really into it but it began to seem as though Elin constantly looked for any reason she could to treat people around her poorly and then whine about how poorly they treated her. I came here to make sure the only likeable character in the book (Will) survives. I absolutely agree with most of the comments below. Hopefully if there are more books Elin grows into someone we can stand.
Haha I love your optimism!!
This story was boring. Who was the anonymous character at the end? I won’t buy a sequel if that is the author’s intention. I rate this book a 5/10.
Hi Jaenne! We are debating who the anonymous guy is: Hayler, or Elin’s dead brother, or someone else. And YES there IS a sequel starring Elin so maybe we will get some answers. I will read the second book just to find out and let you all know what’s up.
Agreed! I am late to the discussion, but I just read the book. I wanted to like it, and it definitely kept me turning pages — but parts didn’t make sense to me. The “hand that really pushed her into the pool” felt like cheating when earlier she had clearly seen Laure’s face on the CCTV footage. And I didn’t ever get any real sense of Laure: she was obsessed enough to essentially stalk Lucas, but that doesn’t have much actual bearing on the plot; rather than calling the police, she disappears and leaves her fiance devastated; where did the blood on the rug come from?; why was she spying on Elin in the changing room? I don’t think everything needs to be neatly explained, but there were too many red herrings and unanswered questions in this one.
Also…maybe this is a personal thing, but I felt like the book stigmatized people who have experienced psychotic depression and sexual assault. Why can’t the killers simply be evil or psychopathic, even if they’re women? I am so over the “girl is raped so she grows up to be a serial killer” trope. Of the many ways sexual violence has life-altering impacts, that has got to be one of the least common in real life, but it’s a convenient and easy — and cliched — motive in fiction. How about something more nuanced?
Hi Monique! You’re not late – welcome!
So many of us agree that there were too many loose ends and things that didn’t make sense. I thought Cecile made more sense as the killer – the whole “last person you suspect” thing (well, that would have been Elin lol) doesn’t work if it’s not set up. And that’s a really good point about Laure. I understand her trauma and frustration and wanting revenge on her rapist but killing all the others didn’t make sense to me.
Oh, I so agree!! I didn’t need anything supernatural, but in deft hands, it could’ve worked.
The epilogue is such crap. It doesn’t jive with anything. Why the Middle Eastern group? So random! Like everything that happened in the novel proper was aimed at Elin.Clunky and disappointing. What a waste of time.
Maybe it is a stretch but the person could be elin and Isaac’s father. All the reader knows about him was he left after Sam died and lost contact. Elin did not get a good look at the persons face at the plunge pool. Only wearing the same thing as Laure in changing room. Laure would know him because of her childhood past and could be working together behind the scenes. Lots of places to hide so he wouldn’t need to shoe his face.
Hi Mollie,
Haha nothing is a stretch after the ending of this one. As for the stalker, I am still Team Hayler, but since there is a second book coming, there are many possibilities. I think her family issues and the Sam story (and even her dad) will probably also be in the second book.
I enjoyed this book so much until Cecile’s reveal. I was even on board with Margot and Lucas…
I had in mind to order a copy to my sister’s place for her because I was enjoying it. Now I doubt I’ll ever recommend it to anyone, sadly!
I don’t see how the person on CCTV could be anyone but Laure, Elin had seen the “pores” of her face!!! The footage was THAT clear!!!
Why did Cecile give her an access card, and play along with the investigation all throughout when originally she’d wanted not wanted anonymity? Because now she wanted to keep going and get five people? Why was Elin so fixated on that one bracelet/patient code, why was the one she happened to take special note of the one that ended up being connected to Margot? Ugh.
What happened to the skier who found Daniel?
Hadn’t Daniel done a lot of the design, and had a lot of the vision? Why was he not mentioned in the press release or given any credit in the book? It was all about Lucas. I thought there would be some motive there, but nothing came of it.
A few more things are bothering me, but like Elin, I can’t “snag” or “hook” onto the thought. Haha.
I am with you! Elin didn’t bother me as much as she bothered other people and I was enjoying the book until it stopped making sense at the end!
Exactly this! Was so into it and then the last few pages and the Epilogue? Plus I’m assuming the setting was still at the Sanatorium?? Why after all the bloodshed? Argh!
Just finished the book and came on here to see comments about that epilogue.
Completely agree good first half and set up and then went downhill as the body count rose.
Elin is crazy. You think she would have learned from nearly dying in the hayler case to not go off again on her own without back up.
Don’t think I’ve got the energy for the sequel…
I’m going to read it and will let you know what I think. I do think this one had promise and then went completely off the rails!
Not sure what to make of the epilogue to be honest, seemed like it was thrown in as an afterthought to plug a possible second book. Possibly just me but was getting tired of people biting down on their bottom lips and wondering how many times staccato was going to be used in one book.
Good point! A common tactic when young adult books were super-hot back in the 2008-2014 era was to stick a cliffhanger at the end of a book so that there could be a sequel or a trilogy. I don’t mind having a series with a book plot arc and a longer series plot arc but there was something odd about the way this was tacked on at the end. The funny thing is that a LOT of commenters can’t stand Elin and probably aren’t that concerned that someone is after her.