“It was a wonderful day for a hike, clear and cool, with just a hint of autumn in the air.”
— Opening line, setting the scene for the girls' fateful hike.

Lois Duncan (1969)
Genre
Thriller / Children's / Mystery / Young Adult
Reading Time
240 min
Key Themes
See below
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When a cryptic phone call shatters the fragile peace surrounding her brother and boyfriend's disappearance, Joan is pulled into a terrifying game of cat and mouse where the truth is far more sinister than their presumed deaths.
Joan and her mother, Mrs. Hammond, are waiting for Joan's younger brother, Frank, and her boyfriend, Larry, to return from a two-week camping trip in the New Mexico mountains. The boys, both experienced campers, are late, causing increasing worry. Mrs. Hammond tries to reassure Joan, but unease grows. When days turn into a week without word, authorities are called, and a search party forms. Despite extensive efforts, no trace of Frank, Larry, or their gear is found. Police conclude the boys likely died in the wilderness or in an accident, a devastating blow to Joan and her mother.
Weeks after the search ends, Joan gets a phone call. The male caller identifies himself as 'Mark' and says he knows what happened to Frank and Larry. He states they are not dead and their disappearance was not an accident. Mark warns Joan not to trust anyone, including the police, and tells her to keep their communication secret. He promises to call again, leaving Joan shocked and confused. This call breaks the fragile peace Joan and her mother had found, bringing back hope but also a terrifying layer of uncertainty and danger.
Mark calls again, giving Joan a coded message. He tells her to decipher it carefully, as it will lead her to the next clue. The decoded message points to a specific location in the high school Frank and Larry attended. Joan, feeling scared but determined, secretly visits the school. Following Mark's instructions, she finds a hidden compartment in a locker. Inside is a unique, hand-carved wooden bird. This discovery confirms Mark is connected to the boys and their disappearance, making the mystery deeper and pulling Joan further into the danger.
As Joan continues her secret investigation, she feels watched. She sees unfamiliar men near her home and following her. These individuals seem connected and are observing her every move. This surveillance confirms Mark's earlier warning about not trusting anyone and shows the dangerous nature of her search. The unsettling presence of these 'others' makes Joan more cautious. She realizes that revealing her knowledge or suspicions could put her, and possibly her mother, in danger. She feels alone, knowing she cannot tell the police or her family.
Mark contacts Joan again with another coded message. This time, the message directs her to a specific park bench at a certain time. Following his instructions carefully, Joan arrives at the bench, trying to act normal while looking for her mysterious watchers. Under the bench, she finds a small, wrapped package. Inside, she discovers a roll of film and a note from Mark, telling her to develop the film herself and not let anyone see what it contains. This discovery reinforces her belief in Mark's claims and the reality of the situation.
Joan, with shaking hands, develops the film in her darkroom at home, following Mark's instructions. As the images appear, she sees photographs of Frank and Larry. They appear alive, though their expressions are unreadable, and their surroundings are unfamiliar. The pictures are grainy and taken from a distance, suggesting a secret operation. This visual proof confirms her brother and boyfriend are alive, but it also deepens the mystery of their disappearance and the danger they are in. The photos make Joan determined to find them, while also increasing her fear of the unknown forces at play.
In a later call, Mark reveals more about the boys' situation. He explains that Frank and Larry found a criminal operation during their camping trip and were framed for a crime they did not commit. This dangerous and powerful organization is holding them captive to ensure their silence and use them as leverage. Mark reveals that the 'Frank' who briefly returned home, reassuring Mrs. Hammond, was an impostor, part of the plan to hide the real Frank's absence. This revelation explains the differences in Mrs. Hammond's memory and confirms the sinister nature of the plot.
Mark, sensing the increasing danger, tells Joan to go to a remote cabin in the mountains, giving her precise directions. He says this is where Frank and Larry are being held, and it is her chance to rescue them. Joan, driven by desperate hope, follows his instructions, driving alone to the isolated place. However, upon arrival, she finds the cabin empty. The men who have been following her ambush her. It becomes clear that Mark has led her into a trap, or perhaps he himself has been manipulated, showing the treacherous nature of her mission and the constant threat she faces.
Joan is captured by the men at the cabin and taken to a secluded location. There, the leader of the criminal organization confronts her. Just as her situation seems bad, Mark appears, revealing his true identity: he is not part of the criminal group, but an undercover agent working to expose them. He explains he had to lead Joan into the trap to gain the criminals' trust and gather evidence. He apologizes for the deception and the fear he caused her, explaining it was the only way to protect her and save Frank and Larry.
With Mark's timely action and the arrival of backup agents, the criminal organization is broken up, and its members are arrested. Frank and Larry are found unharmed, though shaken, after being held captive for weeks. The reunion between Joan, Frank, and Larry is emotional and full of relief. Mark explains the full extent of the criminal operation and how the boys accidentally found it, becoming witnesses and then targets. The family is reunited, and the long nightmare ends. Joan, her mother, Frank, and Larry begin to heal and return to normal life, changed by their experience.
The Protagonist
Transforms from a grieving sister/girlfriend into a determined and resourceful investigator, ultimately helping to rescue her loved ones.
The Supporting
Goes from an ordinary teenager on a camping trip to a captive, eventually rescued and reunited with his family.
The Supporting
Goes from an ordinary teenager on a camping trip to a captive, eventually rescued and reunited with his girlfriend and her family.
The Supporting
Moves from initial optimism to deep grief, then experiences joy and relief upon her son's safe return.
The Supporting
Introduced as a mysterious, untrustworthy informant, revealed to be a heroic undercover agent orchestrating the rescue.
The Mentioned
Appears briefly to deceive Mrs. Hammond, his existence later revealed as part of the criminal conspiracy.
The Antagonist
Remains a shadowy figure, orchestrating criminal activities, until his eventual capture by law enforcement.
The Mentioned
Initially unable to solve the case, they eventually apprehend the criminals thanks to Mark's evidence.
The book begins with the loss and grief Joan and Mrs. Hammond experience after Frank and Larry are presumed dead. The emotional impact of this presumed loss is clear, affecting Mrs. Hammond's fragile state and Joan's desperate search for answers. This theme explores how people cope with tragedy, the hope they hold onto, and the difficulty of accepting an unknown fate. The eventual revelation that the boys are alive contrasts with this initial despair, showing the lasting nature of hope.
“It was impossible to believe they were gone forever. Not Frank, so full of life and mischief, and Larry, with his quiet strength. They just couldn't be.”
A central theme is the constant tension between who to trust and the widespread deception. Mark repeatedly warns Joan not to trust anyone, including the police, forcing her into a solitary and dangerous investigation. The impostor Frank, the surveillance by criminals, and Mark's secret methods all create an atmosphere of paranoia and uncertainty. Joan must learn to tell truth from lies, even from those who claim to help her, making her journey a test of her judgment and strength in a world where appearances deceive.
“Don't trust anyone, Joan. Not the police, not your friends, not even your own shadow. This is bigger than you know.”
Joan's character shows courage and resourcefulness. Despite her fear and great danger, she bravely follows Mark's instructions, deciphers codes, and goes into dangerous situations alone. Her determination to find her brother and boyfriend pushes her beyond what she thought she could do, forcing her to develop skills she did not know she had. She shows great cleverness in navigating clues and avoiding her pursuers, proving that ordinary people can face extraordinary challenges when in serious trouble.
“Fear was a cold knot in her stomach, but the thought of Frank and Larry, out there somewhere, was a hotter, stronger fire.”
The book explores how ordinary events, like a camping trip, can turn into a terrifying criminal conspiracy. Frank and Larry's initial disappearance is thought to be a common outdoor accident, hiding a more sinister plot. This theme shows that danger can exist beneath the surface of everyday life, and that innocent actions can have unexpected and dangerous consequences. It suggests a world where appearances are deceiving, and the ordinary can quickly lead to great peril, forcing characters to confront a reality darker than they imagined.
“Who would have thought a simple camping trip could lead to something like this? It was like a nightmare, but real.”
Drives the plot by providing cryptic clues and warnings.
Mark serves as the primary catalyst for Joan's investigation. His anonymous phone calls and coded messages propel the plot forward, providing Joan with crucial information that the authorities lack. He creates an atmosphere of suspense and mistrust, as Joan (and the reader) is unsure of his true motives or allegiances until late in the story. This device allows for the slow reveal of information, building tension and keeping the protagonist in a state of constant peril and uncertainty, while also providing the necessary guidance for her to uncover the truth.
Engages the protagonist (and reader) in solving the mystery.
The use of coded messages and hidden clues is a classic mystery device that actively involves Joan in the investigation. These clues, such as the location in the high school or the specific park bench, are not immediately obvious and require deciphering, making Joan a proactive participant rather than a passive recipient of information. This device increases the reader's engagement, allowing them to try and solve the puzzle alongside Joan, and builds suspense as each solved clue brings her closer to the truth, or further into danger.
Creates initial deception and a false sense of security.
The 'Impostor Frank' is a crucial plot device used to establish the depth of the criminal conspiracy and to create a false sense of resolution for Mrs. Hammond. By having someone briefly impersonate Frank, the criminals successfully deter immediate suspicion and extensive police investigation, buying them time. This device also serves to highlight the theme of deception and how easily innocent people can be manipulated. When the truth about the impostor is revealed, it retroactively adds a layer of sinister intent to earlier events and validates Joan's growing suspicions.
Generates suspense and a sense of constant danger.
The constant surveillance of Joan by the criminals, and her awareness of being followed, is a key plot device for building suspense and a pervasive sense of danger. It makes Joan's actions feel high-stakes, as any misstep could lead to her capture or worse. This device reinforces Mark's warnings about trust and isolation, forcing Joan to operate in secret and alone. The feeling of being watched creates a claustrophobic atmosphere, emphasizing the power and reach of the criminal organization and the vulnerability of the protagonist.
“It was a wonderful day for a hike, clear and cool, with just a hint of autumn in the air.”
— Opening line, setting the scene for the girls' fateful hike.
“The mountain was a living thing, beautiful and treacherous, and it had a way of keeping its secrets.”
— A general reflection on the mountain's nature, foreshadowing the mystery.
“You never really know someone until you’ve seen them scared.”
— One of the girls contemplates human nature under duress.
“Panic was a cold, creeping thing, and once it got hold of you, it was hard to shake off.”
— Describing the feeling of fear and helplessness during the ordeal.
“The silence was the worst part, the absolute, crushing silence that meant no one was coming.”
— Reflecting on the isolation felt by the lost girls.
“Sometimes the greatest dangers aren't the ones you can see.”
— A realization about hidden threats and the unknown.
“Hope was a fragile thing, easily shattered, but impossible to live without.”
— One of the girls clinging to the belief they might be rescued.
“We were just kids, but the mountain didn't care.”
— A stark realization of their vulnerability against nature.
“The truth was out there, somewhere, if only they knew where to look.”
— Reflecting on the elusive nature of the mystery surrounding the disappearance.
“It’s amazing how quickly you can adapt to the unthinkable.”
— A character observing the human capacity for survival.
“The woods had eyes, or so it felt, watching their every move.”
— Conveying a sense of unease and being observed in the wilderness.
“Memory plays tricks when you're desperate to remember.”
— A character struggling to recall crucial details under pressure.
“They had gone into the woods as children and come out... something else.”
— Reflecting on the transformative and traumatic experience of the survivors.
“The answers weren't always easy, and sometimes, they were terrifying.”
— A general reflection on the resolution of the mystery.
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