100+ Mystery Prompts to Give You Writing Inspiration!

The mystery genre has long been one of the most popular in literature, film, games, and more. Everyone loves a good mystery that’ll keep them guessing, wondering, and exploring! A lot of readers of mystery also enjoy trying to solve the mystery alongside the character. It also opens the door for quite a lot of interesting tales in general. Of course, it can be a bit hard sometimes to come up with ideas and that’s totally understandable! Maybe you just have a feeling for a mystery story but aren’t sure what to fill that feeling with. Well, today, I’ve compiled a list of over 100+ prompts for you to start writing your next mystery book or story!

Check out my other writing prompts: 

• 50+ Romantasy Writing Prompts to Start Your Next Story
• 100+ Fantasy Writing Prompts to Start Your Next Story

1. A detective must investigate a strange and unexplained series or murders where all the victims receive strange letters written in a code before their deaths.
2. A retired police officer uncovers new evidence regarding a case he closed years ago, forcing him to question what he knows and what is real vs fake. 
3. A librarian in a small and strange town discovers a letter inside of a book that unlocks a den of secrets and lies within the town’s city council. 
4. An archaeologist and her team discover an ancient secret that all who have chased after have died.
5. A journalist, investigating the disappearance of a high-profile politician, uncovers a conspiracy that runs deep within the government 
6. A supposedly accidental death at an awards’ show for the rich and famous ends up being a murder, and now everyone at that party is considered a suspect. 
7. A woman inherits a mansion from her late, distant and absent father only to discover that the mansion may be controlled by supernatural entities that were summoned centuries ago. 
8. A private investigator is hired to find a missing person, only to discover that the person never existed, prompting him to investigate whoever hired him. 
9. A police detective must work around his corrupt department to solve a string of serial murders targeting young teens in his town. 
10. A man awakens to having no memory of the past week only to find out that he is a suspect in a murder case
11. A famous writer publishes a new story and the events written within the book uncannily seem to match a real, unsolved crime. 
12. A cold case detective decides to reopen an investigation after new clues were found in the car of a victim. 
13. A young couple moves into a new home, discovering that the previous owners disappeared under strange and mysterious circumstances. 
14. A retired spy must figure out who is targeting her former colleagues and why. 
15. A serial killer targets a major metropolitan city, leaving cryptic clues at each scene, challenging the detectives to catch them. 
16. A private investigator begins to uncover that a dark secret is looming over his own family
17. A warrior in Ancient Rome must determine who is responsible for the murders of several soldiers in his town while navigating the complexities of war. 
18. A cruise ship becomes the scene of a murder and the passengers must try and find out who the killer is before they strike again. 
19. A woman receives anonymous letters that reveal her personal secrets, blackmailing her into doing illegal things in order to keep the secrets hidden. 
20. A detective is framed for a murder he was investigating and must now race against time to prove his innocence. 
21. A famous actor is murdered while filming a new movie and an FBI agent must determine if his death is linked to a string of bizarre and grisly murders in the area. 
22. A young woman finds a hidden room in her apartment, filled with strange occult paraphernalia. 
23. A small-town cop must find out who is kidnapping young girls from the area and making them vanish, but everyone in this town has something to hide, complicating his investigation. 
24. A journalist suddenly receives a tip in her emails one day about a cold case and quickly realizes that someone is stalking her, trying to ensure that the past stays buried. 
25. During a construction dig, workers uncover bones and the bones are linked to a murder from 50 years prior and was never solved. 
26. A museum curator is sent a mysterious letter leading her to a stolen artifact and uncovering a web of lies and murders behind that artifact
27. A detective investigating a series of strange bank robberies uncovers a conspiracy involving high-ranking officials and members of organized crime. A famous artist is found dead and the clues to her murder are hidden in her paintings. 
28. In a world where magic is accepted, a necromancer is hired to help solve murders and other high-profile crimes in the city
29. A young lawyer takes on a case of a wrongful conviction but is now being hunted down by the real criminals in the case
30. A woman wakes up in an abandoned warehouse with no memory of how she got there, next to the body of a dead man.
31. A detective must solve a murder where the only witness is a child who refuses to speak. 
32. A wealthy family’s secrets are suddenly revealed after the patriarch is found murdered in his study. 
33. An orphan suddenly adopted by a rich and mysterious noble family in his kingdom must uncover the mystery of why all other adopted children they took in have mysteriously vanished before. 
34. A detective must solve the mystery of a missing child but discovers that there maybe a paranormal element to the child’s disappearance. 
35. An FBI agent is forced to investigate a series of murders that is copying detail-for-detail  a serial killer case from 200 years ago. 
36. A sheriff must investigate the disappearance of several residents who are all connected by one strange log cabin in the woods 
37. A woman receives a package at her front door that contains evidence from a murder that happened 100 years ago
38. A detective must work with an informant to solve a case involving a major mafia family in the city. 
39. A woman inherits a series of letters from her late mother only to discover that the letters detail the events of a murder that is happening in the present. 
40. A mercenary uncovers a strange town that appears and reappears while he is at war and determines to figure out why that town vanishes at midnight. 
41. A young woman is hired to be a rich family’s stay-in nanny but discovers that not everything is as it seems inside the gilded life. 
42. A journalist investigating a murder uncovers a cult actively trying to summon a demon
43. A woman discovers that her new and seemingly perfect boyfriend is not who he claims to be and that he may be far more dangerous than she thought
44. A private investigator is hired to find a missing painting but is quickly sucked into a web of deceit and lies after discovering that the new owners of the paintings are not real. 
45. A detective and a serial killer work together to solve a new string of murders that closely resemble the serial killer’s MO
46. An FBI agent find out that a place he keeps seeing in his dreams is a real place in his town and upon investigating it, he finds that there are several unmarked graves
47. A high school student in WITSEC is haunted by her family’s crimes and must find out what they did before it’s too late. 
48. A detective must solve a murder where the only clue is a single, untraceable fingerprint 
49. A young woman is found dead in a cemetery, and the investigation reveals she was living under an assumed identity.
50. A detective is called to a murder scene where the victim’s body is arranged in a strange and symbolic way.
51. A man receives a phone call from someone claiming to be his long-lost sibling, leading to a deadly investigation.
52. A woman finds a hidden camera in her home, leading to the discovery of a stalker with deadly intentions.
53. A detective must solve a murder where the victim appears to have been killed by some supernatural forces
54. A woman wakes up to find her husband missing, with no trace of him ever existing.
55. A woman’s husband disappears, and her search for him reveals a life she never knew he had.
56. A young woman is kidnapped and wakes up on a private island where she is forced to play along with her twisted kidnapper’s scavenger hunt 
57. A detective is called to investigate a murder at a historic hotel, where the past seems to be repeating itself.
58. A private investigator is hired to follow a spouse but ends up finding the spouse murdered
59. On Halloween night, a woman discovers that the Headless Horseman might not be a simple urban legend
60. A young woman is found dead in a library, and the clues to her murder are hidden in the books she was reading
61. A detective must solve the mystery of a series of murders where the victims all share the same unusual birthmark.
62. A detective must solve the mystery of a man who appears to have committed suicide, but evidence suggests otherwise.
63. A wizard is being charged with murder and it’s up to a brave knight who believes him to acquit him of the charges before the wizard is hanged
64. A detective must solve the mystery of a man who disappeared without a trace, leaving behind a trail of clues.
65. A detective must solve the mystery of a series of deaths that all occur on the same date each year.
66. After several members of the CIA end up missing, a team of FBI agents is called in to figure out where the CIA agents have gone to
67. A young couple’s dream vacation turns into a nightmare when they discover a body in their hotel room.
68. After the princess goes missing, a team of dark magic-wielding mercenaries are hired to find her
69. A young woman is found dead in a park, and the investigation reveals she was living under an assumed identity.
70.  A detective is called to a remote mountain lodge where a guest has been murdered during a snowstorm, and the killer is among them.
71. A detective is called to investigate a murder at a masquerade ball where no one knows the true identity of the guests.
72. An investigator who specializes in organized crime is forced to investigate a mass murder event after an entire branch of crime in the city is killed off by a new threat
73. A woman receives a phone call from her deceased mother, but the voice at the other end is not her mother
74. A young woman’s search for her missing brother leads her into the dark underworld of a big city where she finds that her brother may not have been as innocent as he claimed to be
75. A woman discovers a photograph of herself as a child in a stranger’s house, leading her to question her entire past.
76. A detective must solve the mystery of a series of robberies where the thief leaves behind a single rose and a vial of blood
77. A detective investigating a murder finds out that there may be time traveling hitmen involved
78. A detective is called to investigate a series of murders where the victims are all members of the same secret society at a university
79.  A woman’s search for her birth parents leads her to uncover a dark family secret that traces back to medieval times and someone is very willing to kill to make sure that secret stays a secret
80.  A detective must solve the murder of a judge, and all the suspects are people they’ve sentenced in the past.
81.  A detective is called to investigate a murder in a remote village where the locals believe a supernatural force is responsible.
82. A team of ghost hunters uncovers a dark secret inside the home of a wealthy business owner whose life may not have been so lovely
83. A detective is called to a crime scene where the victim was killed in a method that matches a famous unsolved case from decades ago
84. A soldier coming home from war finds out that his entire neighborhood has vanished and finds clues hidden in the basement of his home
85. A man moving to a new neighborhood finds a body in his garage and is now the prime suspect in the murder of a person who went missing thirty years ago
86. A father must find out what happened to his son after his son was last seen with a strange man dressed like a clown
87. An FBI agent hunting down a serial killer finds out that the killings may match a series of murders that occurred in medieval times and his ancestor was an investigator in that case
88. A woman’s husband is murdered and she is determined to solve the case but ends up discovering that he may have been involved in something dark and dangerous
89. A young woman receives a series of love letters but the letters are written in the same style as a serial killer who existed over a hundred years ago
90. A man receives an anonymous tip that leads him to uncover a conspiracy within his own company
91.  A man wakes up to find that his entire life has been erased and that his identity has been stolen by a malevolent spirit
92. Two teens discover a gun in their backyard and suddenly, their homes become possessed by dark spirits
93. A royal advisor is murdered during a peace treaty negotiation between two rival kingdoms, and the investigation uncovers ancient magic tied to the crime
94. A magical academy is thrown into chaos when a student is found petrified by an unknown spell, and the investigation reveals a secret society within the school
95. A powerful sorceress is murdered in her impenetrable tower, and her apprentice discovers that her death is linked to a long-lost magical relic hidden in a forgotten realm
96. A series of ghost sightings coincide with the discovery of a hidden mass grave, and a detective must uncover the identities of the victims and why they have become ghosts 
97. A town is cursed with a never-ending fog, and anyone who enters it disappears without a trace. A soldier decides to enter the fog to figure out why it’s there
98. A man traveling has his car break down in a strange town but realizes that there are lots of cars tied to missing persons in that exact town
99. A woman is plagued by recurring nightmares of a murder, only to realize that the dreams are visions of a crime that is yet to happen
100. A small town is terrorized by a series of gruesome murders, each victim found with a missing body part. A detective discovers that the killings are part of a ritual to summon an ancient evil
101. A serial killer is on the loose, but all the evidence points to a man who has been dead for over a decade. The police must solve the mystery of how a dead man is committing these crimes
102. A man receives a package containing an old, cursed Aztec artifact and everyone around him begins to die in horrific ways that were detailed in an old priest’s journal
103. A detective must find out why a newly opened hotel is the sight of deaths where each victim’s final moments are captured on camera, showing them being chased by something that doesn’t appear to be there
104. A nobleman is found dead in his mansion and his wife soon after, leading his daughter to discover a hidden world of assassins, sorcerers, and secret societies
105. A woman gets a security box at a bank but discovers that several passports have been left in there, each one with a picture of her face in it

Hopefully these prompts can help inspire you to start writing your own mystery story! Before you head on out, be sure to check out my series, The Fallen Age Saga, and don’t forget to sign up for my newsletter so you can get updates on all my latest WIPs, book releases, posts and more!