Mystery Writing Prompts
Every clue tells a story
The best mysteries are fair — every clue the detective needs is available to the reader. That's also the hardest part of writing one. These prompts give you a crime, a setting, and suspects worth investigating. FictionMaker's AI helps you track clues, alibis, and timelines so your mystery plays fair.
The Locked Bakery
A famous pastry chef is found dead in her bakery's walk-in freezer — locked from the inside. No one has a key. The security footage shows no one entering or leaving. The only clue: a cake she wasn't scheduled to bake.
The Book Club Murder
A member of a small-town book club is murdered. The murder method matches the crime in the book they were reading that month. It's the third month in a row.
Inheritance Mystery
A billionaire dies and leaves her fortune to her cat. Her three children each have motive, means, and opportunity. The twist: the billionaire changed her will the day she died — and the lawyer who witnessed it has disappeared.
The Reunion
At a college reunion, someone is poisoned at dinner. All twelve attendees at the table had a reason to want the victim dead — including you. You have six hours before the police arrive. The roads are washed out.
Cold Case Podcast
Your true-crime podcast investigating a 30-year-old disappearance is getting too popular. The missing person's family wants you to stop. The police want you to stop. Someone just left a box of evidence on your doorstep that changes everything.
The Art Heist
A priceless painting is stolen from a museum during a gala attended by 500 people. The painting was replaced with a perfect forgery — so perfect that no one noticed for a week. You're the forger, and you didn't do this one.
Murder at the Inn
A snowstorm traps eight guests at a remote inn. By morning, one is dead. The innkeeper's guest register lists nine names, not eight. Someone was never supposed to be here.
The Ghost Writer
A bestselling mystery author dies mid-series. A ghostwriter is hired to finish the final book. While reading the author's private notes, the ghostwriter realizes the unsolved mystery in the books is based on a real crime — one the author committed.
Vanishing Act
A street magician performs a disappearing act in broad daylight and actually vanishes. No trick, no trapdoor, no explanation. She's been missing for 72 hours. The only lead: a playing card left behind with a phone number on it.
The Neighbor's Dog
Your neighbor's dog digs up a bone in their backyard. It's human. Your neighbor isn't surprised — they calmly take the bone inside and close the blinds. You're a retired detective. This is the house next door.
The Anonymous Tip
An anonymous tip leads police to a body that's been hidden for years. You're the detective on the case. The tipster knew details that were never made public. The tip came from your phone number — but you didn't make the call.
Museum Theft
A night guard at a museum discovers that a famous sculpture has been replaced by an identical copy — made from bone. Human bone. Carbon dating says the bones are 200 years older than the sculpture.
The Will
A family gathers for the reading of their mother's will. She leaves each child a sealed envelope. Inside each envelope is evidence of a crime committed by one of the other siblings. Mother wanted the truth to come out — but which truth?
The Train
A passenger dies on an overnight train. The train has no stops for six hours. Everyone is a suspect. The victim's phone shows they sent a message to someone on the train: 'I know what you did.' The message was sent to a number no one claims.
The Translator
A translator working on a centuries-old manuscript realizes it contains directions to a hidden room in a cathedral. The room exists. Inside is a body — fresh. The manuscript was written in 1423.
Small Town Secret
A journalist moves to a small town where everyone is suspiciously nice. Crime rate: zero. Poverty: zero. Everyone smiles. She investigates and finds that no one has left the town in 15 years. And no one can explain why.
The Double
A woman reports herself missing. She walks into a police station and says someone who looks exactly like her has taken over her life — living in her house, going to her job, sleeping next to her husband. Her husband says nothing has changed.
Wedding Murder
The bride is found dead in her wedding dress an hour before the ceremony. The groom, the maid of honor, and the bride's mother each confess to the murder — separately, with three different methods.
The Alibi Network
You discover a service that provides alibis for a fee — convincing witnesses, fake receipts, fabricated security footage. Someone used the service the night of a murder. You're the investigator — and the alibi they bought places them at dinner with you.
Library Secrets
A librarian finds a note hidden in a returned book: 'If you're reading this, I'm already dead. The answer is in the Dewey Decimal system. 364.152.' The Dewey number for homicide. The book was last checked out by a police officer.
Frequently Asked Questions
How do I write a fair mystery?
A fair mystery gives the reader every clue they need to solve it before the detective does. Plant clues naturally in dialogue and description, use red herrings to misdirect, and make sure the solution is surprising but inevitable in hindsight. AI can help track which clues have been revealed.
What's the difference between a cozy mystery and a hard-boiled mystery?
Cozy mysteries are set in close-knit communities (small towns, bookshops, bakeries), feature amateur detectives, and avoid graphic violence. Hard-boiled mysteries feature cynical professional detectives, urban settings, and don't shy away from violence and moral ambiguity.