The Bachelorette Party by Camilla Sten Summary, Characters and Themes
The Bachelorette Party by Camilla Sten is a dark and atmospheric psychological thriller set on a secluded island in the Baltic Sea. The novel follows the intertwining stories of several women who come together for a seemingly innocent bachelorette party.
What begins as a celebration soon spirals into a chilling mystery, as the island holds secrets from the past that are about to resurface. Themes of grief, obsession, friendship, betrayal, and unresolved trauma run deep throughout the story. As the women confront their personal demons and the island’s dark history, they find themselves trapped in a web of danger and deception.
Summary
Matilda and her group of friends have been gathering for years for an annual trip to Isle Blind, a secluded island in the Baltic Sea. This year, however, the trip carries a heavier weight.
Matilda, who once relished the wild adventures of youth, finds herself reflecting on the changes in her life. Now engaged to Carl and pregnant with his child, she feels torn between the woman she used to be and the adult life she’s created.
Her feelings of nostalgia are further complicated by a secret she’s keeping: her pregnancy. She struggles with the idea of motherhood and what it might mean for her future.
As the group enjoys their time on the island, old tensions and unresolved emotions bubble to the surface. Matilda is particularly wary of her friend Anna, who seems to sense the secret she’s hiding.
One night, Matilda finally confides in Anna about her pregnancy, unsure of what it means for her relationship with Carl and her future. Anna’s reaction is supportive, but Matilda remains uncertain and anxious about the choices she faces.
But the atmosphere on the island shifts dramatically when the group is shaken by the discovery of a body—Linnea, one of their own, is found lifeless on the beach, brutally murdered. Shock and fear ripple through the group as they try to comprehend what has happened.
The tension heightens when Matilda discovers that Anna, too, has been attacked by a mysterious figure in black. The group is plunged into chaos as the figure appears again, wielding a knife and threatening to kill everyone in sight.
As Matilda tries to make sense of the situation, she finds herself paralyzed by fear and indecision. The situation escalates when the figure turns the knife on Matilda herself, delivering a blow that leaves her with a terrifying sense of clarity before the pain sets in.
Meanwhile, the story introduces a second narrative thread centered on Tessa Nilsson, a podcast host with a troubled past. Tessa has been researching true crime stories for years, and she becomes particularly fascinated by the unsolved disappearance of the Nacka Four, a group of women who disappeared near Isle Blind ten years ago.
Tessa’s interest in the case is both professional and personal, as she seeks to revive her faltering career while grappling with the fallout from a failed relationship with her former producer, Minna.
Tessa, accompanied by her sister Lena, arrives on Isle Blind for a luxury bachelorette party, but she cannot escape the weight of her emotions and unresolved issues. The island’s eerie beauty contrasts with Tessa’s inner turmoil as she tries to enjoy the festivities while being drawn into the mystery of the Nacka Four.
She begins to suspect that the disappearances are connected to the events unfolding on the island and that the truth may be far darker than she imagined.
As the weekend progresses, Tessa’s investigation into Matilda’s disappearance intensifies. She feels a growing sense of dread and unease, sensing that the island’s dark past is intertwined with the events of the present.
Tessa’s interactions with her friends and the hotel owner, Irene, become increasingly strained as she tries to uncover the truth. Irene is visibly affected by any mention of her sister Matilda, but remains guarded and reluctant to discuss the past.
Tessa’s sense of isolation and guilt grows as the weekend continues. Conversations about relationships, children, and life choices stir up unresolved emotions.
At the same time, Tessa is determined to find out what happened to Matilda and the Nacka Four. She begins to fear that the island may hold even more dangerous secrets than she anticipated.
The mystery deepens when Tessa discovers a photo of Irene and her late sister Matilda in an office on the island. The photo shows Matilda looking very much alive, a stark contrast to the tragic image of her death.
Tessa’s investigation leads her to an account labeled “Staff” on a computer, but her search is interrupted by Adam, a figure who appears to be both calm and apologetic, yet leaves Tessa fearful of his intentions.
The tension continues to rise as Tessa tries to warn her friends of the danger lurking on the island. She senses that one of them might be in immediate danger, and her fears are confirmed when she stumbles upon Caroline’s body in a dinghy, showing signs of a brutal murder.
Tessa is shaken to the core, but she tries to stay composed as she tries to alert the others and figure out how to get off the island. However, her phone dies before she can contact anyone, further compounding her fear and sense of helplessness.
As the night progresses, Tessa becomes increasingly paranoid, convinced that the killer is targeting them one by one. Her anxiety intensifies as she realizes that she may be next.
The friends try to maintain some semblance of normalcy, but the fear and tension are palpable. Tessa’s desperation to uncover the truth about Matilda’s death and the island’s dark secrets only grows, as does the sense of danger that surrounds them.
The plot reaches a chilling climax when Irene’s true intentions are revealed. Irene, driven by grief and a desire for revenge, has turned into a ruthless and vengeful figure.
She begins targeting those she believes are responsible for her sister’s death, including Anneliese, a close friend of Matilda’s. Irene’s actions become increasingly violent, and Anneliese finds herself at the mercy of Irene’s wrath.
Tessa watches in horror as Irene’s grief-driven obsession escalates into a deadly spiral of violence.
The novel culminates in a devastating showdown, where the consequences of the characters’ actions come to light. Tessa, filled with guilt and fear, is forced to confront the horrors of the past and the destruction caused by revenge.
The island’s dark history and the tragedies it has witnessed are revealed in their full, horrifying scope. Tessa is left grappling with the aftermath of the violence, her life forever changed by the events that unfolded on Isle Blind.
The novel ends on a somber note, leaving Tessa with the emotional scars of a past that cannot be outrun, and a future forever shaped by the island’s dark legacy.

Characters
Matilda Sperling
Matilda is one of the central figures in The Bachelorette Party, and her complex emotional journey drives much of the story’s tension. A woman who has moved from youthful rebellion to a more grounded, but less adventurous adulthood, Matilda is deeply conflicted.
On the one hand, she finds comfort in the stability of her life with Carl, her fiancé. On the other hand, she longs for the carefree freedom she had in her youth.
The trip to Isle Blind, a place tied to her past, stirs up feelings of nostalgia and discomfort. Matilda is also hiding a secret: she is pregnant, a revelation that adds to her anxiety about the future.
This pregnancy forces her to grapple with her sense of self and the fear of losing the life she once knew. Her relationship with her friends is strained and tinged with unspoken emotions, but it is her tragic death, discovered by Matilda’s friends during their stay, that truly sets the darker events of the island into motion.
Tessa Nilsson
Tessa is a character struggling with both professional and personal turmoil. A podcast host who has found herself in the midst of a career slump, she is drawn to the mystery of the Nacka Four—a group of women who mysteriously disappeared near Isle Blind, including Matilda Sperling.
Tessa’s investigation into their disappearance becomes intertwined with her own emotional baggage, especially her complicated relationships with friends and past mistakes. Her guilt and feelings of inadequacy permeate her actions, especially as she bonds with her friends during the luxury bachelorette trip to Isle Blind.
While trying to solve the mystery, Tessa’s suspicions grow, and her personal insecurities are constantly tested. Throughout the story, Tessa’s growing fear of the island’s dark past intertwines with her attempts to make sense of her own unresolved feelings of guilt and failure.
As the suspense escalates, Tessa’s internal journey mirrors the terrifying, escalating danger around her.
Irene
Irene plays a pivotal role in the dark twist of The Bachelorette Party, particularly as she becomes consumed by grief and vengeance. She is the sister of Matilda, whose death she cannot reconcile with.
Irene’s pain morphs into an obsession, particularly as she believes some of Matilda’s friends—like Anneliese—are complicit in her death. Irene’s grief transforms her into a cold, manipulative figure, capable of violent and unpredictable acts as she exacts her revenge.
She is aided by Adam, who becomes her accomplice, but Irene’s emotions are raw and untamed. Initially, she appears as a woman driven by love and loss, but as her revenge spirals out of control, it becomes evident that Irene has been consumed by her grief, and her actions are driven more by anger than reason.
The violence she inflicts on Anneliese and others becomes a chilling reflection of the consequences of unprocessed grief and the destructive force of revenge.
Anneliese
Anneliese is caught in the chaotic web of revenge spun by Irene, Matilda’s sister. While initially seen as a carefree, vibrant character, Anneliese’s life takes a tragic turn as she becomes the target of Irene’s obsessive vendetta.
The once-strong friendship between Anneliese and Matilda is torn apart by Irene’s belief that Anneliese is somehow responsible for her sister’s death. Anneliese’s vulnerability becomes painfully apparent when she is bound and threatened by Irene, and her fear is palpable.
Her strength as a character is tested to its limits, and she is forced into a desperate fight for survival. The shift in her character—from a lighthearted figure to a terrified victim—adds depth to the emotional stakes of the story.
Anneliese’s fate serves as a tragic consequence of the escalating violence and revenge on Isle Blind.
Adam
Adam, an accomplice to Irene in her quest for vengeance, is a character whose motivations and loyalties remain ambiguous. He appears to be passive at times, almost caught in the undertow of Irene’s obsessive grief.
While initially appearing to simply support Irene, Adam is visibly shaken by the escalating violence and the impact of Irene’s actions. His passivity shifts as he begins to realize the full extent of Irene’s madness, but he is ultimately complicit in the violence that ensues.
Adam’s internal struggle and his fear of the consequences of Irene’s actions add complexity to his character. Although he is not as consumed by rage as Irene, Adam’s actions reflect his inability to break free from the vortex of revenge and the twisted consequences that follow.
Carl
Carl, Matilda’s fiancé, is a more passive character in The Bachelorette Party, yet his role in the narrative is crucial. His presence in Matilda’s life represents the stability and normalcy that Matilda longs for, but it is also the source of her conflict.
Carl’s relationship with Matilda is one of quiet acceptance, yet he remains oblivious to the turmoil she is experiencing regarding her pregnancy and her desire for the past. Carl’s connection to the darker events on Isle Blind—particularly his relationship with Matilda—becomes more significant as the story unfolds, but his character is largely defined by his distance from the chaos and violence that takes hold of the island.
His inability to fully understand or intervene in the mounting danger makes him a character who contrasts sharply with the emotionally-driven and violent characters around him.
Natalie
Natalie, a friend of Tessa and a part of the group visiting Isle Blind, is introduced with a sense of vulnerability. As the danger on the island escalates, Natalie becomes one of the characters most at risk.
The tension surrounding her is heightened by her isolation from the group at critical moments. While not as deeply involved in the investigation as Tessa, Natalie’s fate is central to the unfolding mystery, and her presence adds to the growing sense of dread that envelops the group.
As the narrative progresses, the focus on Natalie shifts from her role as a background character to one of significant danger, especially as she becomes a potential target of the killer.
Themes
Grief and Revenge
In The Bachelorette Party, grief emerges as a dominant theme, not merely as an emotional response but as a driving force that shapes characters’ actions and decisions. Irene’s transformation from a grieving sister to a cold, vengeful figure highlights the destructive potential of unresolved sorrow.
Her sister Matilda’s death becomes the catalyst for Irene’s descent into madness. Instead of processing her pain in a healthy manner, Irene allows her grief to morph into an obsession, which eventually blinds her to the consequences of her actions.
The narrative presents revenge not as a simple reaction to loss, but as an all-consuming desire that obliterates any semblance of reason or morality. This is underscored by Irene’s violent actions toward Anneliese, Matilda’s friend, whom Irene holds accountable, even if unjustly, for her sister’s demise.
In her relentless pursuit of vengeance, Irene becomes a shadow of the person she once was, consumed by bitterness and hatred. The role of grief as a form of obsession is also reflected in Tessa’s journey.
She grapples with her own guilt and past mistakes, but unlike Irene, she attempts to seek redemption rather than succumb to destructive emotions. However, Tessa too is deeply affected by the violent acts that unfold, haunted by the trauma and loss.
The theme suggests that unresolved grief, when allowed to fester and become obsessive, can lead to an irreversible spiral of pain and destruction, not just for the individual but also for those around them.
Friendship and Betrayal
The relationships between the women in The Bachelorette Party reveal complex dynamics, especially in terms of how friendship can be tested and even fractured over time. Matilda’s bond with her friends initially seems unbreakable, but as the story progresses, underlying tensions and secrets begin to surface, altering the nature of their connections.
Matilda, burdened by her own hidden fears and secrets, particularly about her pregnancy, struggles to maintain authenticity with her closest friends. This creates a subtle form of betrayal, not necessarily in the traditional sense, but in the emotional distance she places between herself and the people who were once closest to her.
Similarly, Irene’s perception of betrayal is heightened when she directs her wrath toward Anneliese, believing that her friend’s involvement—whether real or imagined—contributed to Matilda’s fate. The theme of betrayal is explored as a slow, insidious erosion of trust, where each character harbors personal regrets, guilt, and unresolved issues with their friends.
These betrayals are not always overt but are instead expressed in moments of silence, avoidance, and miscommunication. Even Tessa, who initially joins the island trip with her own personal struggles and unresolved relationships, finds herself confronted by the weight of her past mistakes with her friends, making her increasingly aware of the delicate balance between loyalty and betrayal.
Ultimately, the story presents betrayal as a theme that transcends isolated acts and instead explores how time, secrets, and emotional wounds can cause the delicate fabric of friendship to unravel.
The Passage of Time and Nostalgia
Time and nostalgia shape much of the character development in The Bachelorette Party. For Matilda, the island trip serves as a poignant reminder of her past—a time when she was carefree, rebellious, and full of youthful ambition.
The tradition of returning to the island each year marks significant milestones in her life, with each trip acting as a checkpoint of sorts. Yet, it is clear that time has changed Matilda.
Her nostalgia is bittersweet, as she longs for the freedom and excitement of her youth but feels conflicted by her present, more settled life. This longing for the past, while comforting, also highlights her sense of loss—of the person she once was and the life she might have lived.
For Tessa, the passage of time is a source of both reflection and regret. Her investigation into the island’s history, particularly the disappearance of Matilda and the Nacka Four, forces her to confront the passage of time in a different way, as she uncovers layers of unresolved mysteries and deep emotional scars.
The sense of time slipping away is heightened by the tragic events unfolding on the island, where the present collides with the unresolved past. The theme of nostalgia is intertwined with a sense of inescapable change, as the characters find themselves unable to fully reconcile their pasts with their current lives.
The island itself, with its haunting beauty and hidden history, becomes a symbol of this tension between past and present, embodying the haunting power of time and how it shapes both the individuals and the world around them.
Isolation and Paranoia
The setting of Isle Blind, a remote and secluded island, plays a pivotal role in creating a sense of isolation and growing paranoia throughout the narrative. As the story unfolds, the isolation of the island becomes more than just a physical reality—it becomes a psychological state that weighs heavily on the characters.
Tessa, in particular, feels the isolation acutely, as she struggles with both her personal demons and the growing sense that something sinister is unfolding. The island’s beauty, initially alluring, transforms into something oppressive, and the sense of being cut off from the outside world amplifies the characters’ fears and suspicions.
As tensions rise, the characters find themselves questioning each other’s motives, and trust quickly erodes. Tessa’s paranoia intensifies as she uncovers more unsettling truths about the island’s past, feeling increasingly hunted by an invisible threat.
The island’s remoteness makes it the perfect setting for psychological unraveling, where the characters’ anxieties are magnified by their inability to escape or seek help. This theme explores how isolation—whether physical, emotional, or psychological—can distort perception, heightening the fear of the unknown and making the characters more susceptible to panic and suspicion.
The island becomes a microcosm of a larger societal breakdown, where the veneer of civility is stripped away, and survival instincts take over.
Identity and Self-Perception
The theme of identity is closely linked to the characters’ internal struggles and how they perceive themselves in relation to others. For Matilda, her trip to Isle Blind forces a confrontation with her own identity.
The traditions of the island, which once symbolized carefree adventures and youthful rebellion, now serve as a mirror reflecting how much she has changed. Matilda’s internal conflict is rooted in her struggle to reconcile the woman she has become with the person she once was.
The sense of losing one’s identity is further explored through Matilda’s secret pregnancy, which symbolizes her fear of being tied to a future that might stifle her autonomy. Similarly, Tessa’s journey is one of self-discovery as she contemplates her own identity in the wake of personal failures.
Her investigation into the island’s dark history and her role in the unfolding events forces her to grapple with her own sense of guilt, self-worth, and purpose. The narrative also examines how characters are often shaped by the perceptions of others, and how the lens through which they view themselves can be distorted.
The theme of identity is not only explored through the characters’ personal histories but also through the way they react to the unfolding mystery. As the tension on Isle Blind escalates, the characters’ responses reveal the complexity of their inner worlds, where their actions are often driven by a need to prove themselves or to regain control over their lives.
Ultimately, the story emphasizes how fragile identity can be, particularly when individuals are faced with traumatic experiences or life-altering events that challenge their sense of self.