★ CASE ACTIVE     ★ DO NOT CROSS     ★ EVIDENCE SEALED     ★ DETECTIVE ACCESS ONLY     ★ CASE ACTIVE     ★ DO NOT CROSS     ★ EVIDENCE SEALED     ★ DETECTIVE ACCESS ONLY     ★ CASE ACTIVE     ★ DO NOT CROSS     ★ EVIDENCE SEALED     ★ DETECTIVE ACCESS ONLY     ★ CASE ACTIVE     ★ DO NOT CROSS     ★ EVIDENCE SEALED     ★ DETECTIVE ACCESS ONLY    
New case drops every week

AI-generated murder mysteries you solve
like a real detective.

Witness statements. Forensic reports. Suspect dossiers. Red herrings. You read the evidence, cross-reference the alibis, and name the killer. No boxes to ship. No waiting. Just cases.

Free case requires no account  ·  Full investigation  ·  ~10 minutes

∞ Unique Cases
3 Difficulty Levels
$9.99 Starts At
How It Works

Three steps. One killer.

Step 01

Get Your Case

Every week, a fresh AI-generated murder mystery lands in your case files. Opening scene. Victim profile. Suspects. Forensics. The full dossier — instantly.

Step 02

Investigate

Read witness statements. Examine forensic reports. Challenge suspects. Check timelines. Cross-reference every detail — because the killer buried something in the evidence.

Step 03

Solve It

Name your suspect, their method, and their motive. Then reveal the full solution. See exactly how the real killer did it — and where your deduction led you right (or wrong).

Sample Case File

This is what lands in your inbox.
Can you spot what's wrong?

■ Case File #0247 — Active Difficulty: Easy  |  Est. solve time: 10 min
The Harborside Arrangement
Victim: Eleanor Voss, 54  |  Scene: Private residence, 14 Harborside Lane

Eleanor Voss was found dead at approximately 11:52 PM on Thursday. Medical examiner places time of death between 10:30 PM and midnight. Cause of death: blunt force trauma to the posterior skull. No signs of forced entry. The front door was locked from the inside — except the ██████████████████████████████ which the responding officer noted was ███████████████.

Three individuals had access to the property that evening. Phone records show a call placed to an unregistered number at 10:02 PM, lasting 22 seconds. The caller's identity has not yet been confirmed, but cell tower data places them within ████████████████████ of the scene.

Witness Statement
"I heard the front door at 11:40. I know because the news had just ended. But Marcus said he was home all night."
Forensic Report
Traces of saltwater residue on victim's shoes. Nearest coast: 12 miles from reported location of death.
Phone Records
Three calls to an unregistered number, 9:15 PM – 10:02 PM. Each under 30 seconds. Last call never returned.
MH
Marcus Harlow
Husband
DP
Diana Price
Business Partner
TK
Thomas Kearns
Neighbor
🔒
5 more evidence items sealed. Suspect confrontation transcripts, full forensic pathology report, and security footage analysis are gated behind your investigation actions. Unlock this case →
Membership

Pick your case load.

Every plan includes a new AI-generated murder mystery each week. Cancel anytime.

Basic
$9.99 /mo

For the casual detective. One new mystery each week, full investigation experience.

  • ✓ 1 AI mystery per week
  • ✓ Full case files with all evidence
  • ✓ Interactive investigation system
  • ✓ Easy, Medium & Hard difficulty
  • ✓ Solution reveal & deduction chain
  • ● Featured Favorites gallery
  • ● Create Your Own Mystery
Get Basic
Most Popular
Pro
$14.99 /mo

For the dedicated investigator. Everything in Basic plus access to the curated case gallery.

  • ✓ 1 AI mystery per week
  • ✓ Full case files with all evidence
  • ✓ Interactive investigation system
  • ✓ Easy, Medium & Hard difficulty
  • ✓ Solution reveal & deduction chain
  • ✓ Featured Favorites gallery
  • ● Create Your Own Mystery
Get Pro
Premium
$19.99 /mo

For the master sleuth. Everything in Pro, plus build and submit your own AI mysteries.

  • ✓ 1 AI mystery per week
  • ✓ Full case files with all evidence
  • ✓ Interactive investigation system
  • ✓ Easy, Medium & Hard difficulty
  • ✓ Solution reveal & deduction chain
  • ✓ Featured Favorites gallery
  • ✓ Create Your Own Mystery
  • ✓ Submit for featuring
Get Premium
Feature Basic
$9.99/mo		 Pro
$14.99/mo		 Premium
$19.99/mo
AI mysteries per week111
Full evidence case files✓✓✓
Interrogate suspects✓✓✓
3 difficulty levels✓✓✓
Solution reveal & deduction chain✓✓✓
Featured Favorites gallery—✓✓
Create Your Own Mystery——✓
Submit mysteries for featuring——✓

All plans renew monthly. Cancel anytime, no questions asked.
Not ready to subscribe? Buy a single case for $1.99 → — or try the free case first →

Why ColdFile

Digital beats cardboard.
Every time.

Physical Mystery Boxes
✕ $25–$40 for one case
✕ Wait 1–3 weeks for shipping
✕ Same case as everyone else
✕ Finite supply, sells out
✕ One difficulty level
✕ Can't replay; once you see the answer it's over
VS
ColdFile
✓ From $9.99/month
✓ Instant access, solve anytime
✓ Every case is AI-generated and unique
✓ Unlimited mysteries, no stock
✓ Easy, Medium, or Hard — your call
✓ Endless new cases every week

The case is open.
The clock is running.

"73 million Americans listen to true crime. They consume stories. ColdFile lets them live one — every week, a new murder, a new chance to prove they'd have caught the killer."

No signup needed for the free demo. Subscriptions from $9.99/mo.