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A woman at home at night, looking up at a case wall of photos and red string, a laptop on her knees
Games like Hunt A Killer, played online

The case file, without the box.

Loved spreading a Hunt A Killer file across the table? This is the same kind of game in your browser. Open a case tonight.

Choose a case →Play a free case
  • No box, no shipping
  • No subscription
  • From $7.99 a case, pay once

what fans will recognise

The best part of a mystery box is the investigation. That is the whole game here.

Reading the evidence closely, building the timeline, catching the detail that doesn't fit, and finally naming the killer. Each case is a file you work through yourself, with nobody telling you what to think.

In every case fileComplete
  1. Witness statements and police reports that don't quite agree
  2. Scene photos, reports, receipts and records
  3. The phones, inboxes and messages of the people involved
  4. Interviews where suspects lie, and change their story when you show them evidence
  5. Tools to decode messages, read photo data, clean up audio and search a computer
  6. The charge: name the killer and how they did it. Get it wrong and the case stays open

Box or browser

How it's different from a box

An honest list, including what you give up.

A mystery box in the postDetectiveOS
Getting startedOrder it, then wait for the postOpen a case tonight. Nothing to wait for or ship
PayingOften sold as a subscription$7.99 a case, paid once. No subscription
The storySome stories run across several boxesOne complete case and its own solution, in an evening or two
The evidencePaper you can hold and spread out on the tableThings a box can't hold: recordings, phones, inboxes, a suspect's computer
The suspectsYou read what they saidYou question them, catch the lie and press them with evidence
AfterwardsPieces to keep track of and tidy awayProgress saves. Nothing to lose down the back of the sofa
What you give upThe surprise of a box arriving, and paper in your handsA laptop or desktop is needed to hand in evidence. A whole case can't be finished on a phone yet

We only describe mystery boxes in general here; each box company does things its own way.

Which case to open

Pick by what you liked in a box

All 8 cases
A big cast and a proper whodunitThe Wolf FeastMediumA locked-room puzzleLast Train to MeridianExpertA storm and an isolated settingThe Lighthouse SignalMediumCodes, key cards and locked filesRoom 17ExpertPhones, DMs and digital trailsInfluencer HouseHardA heist with a twistEight MinutesHardA missing person and a timeline to rebuildThe VanishingMediumExpert level, no hand-holdingBlack Ice PortExpert

Three files fans open first

See all 8
New

The Wolf Feast

Twelve people drank from the same cup at a castle feast. Only one of them was meant to die.

Medium · 2 h$7.99
New

Eight Minutes

The heist of the century took eight minutes. The diamonds were fake.

Hard · 2 h$7.99

Last Train to Meridian

A man dies on a night train, in a cabin latched from the inside. The crew insists it was medical.

Expert · 2½ h$7.99

One case for $7.99, any 3 for $16.99, or all 8 for $35.99. Pay once, keep them.

A couple on a sofa at night working a case on a laptop

like a box on the kitchen table

Better with two.

Put the case on one screen and argue it out on the sofa, or share the screen on a call. One of you reads the statements, the other checks the photos.

How it works as a game for couples →

Questions from Hunt A Killer fans

Is DetectiveOS a subscription, like a mystery box?

No. Each case is a one-time purchase and complete on its own: one case, one solution, played in one or two evenings.

Do I need to print anything?

No. All the evidence is on screen: documents, photos, recordings, phones and inboxes. Nothing is printed or shipped.

Can I play with a partner or friends?

Yes. Put it on one screen and solve it together, or share your screen on a call. Playing as a couple

How long is a case?

About 1½ to 2½ hours. Your progress saves, so you can split a case over two evenings.

Which case is the easiest?

Start with The Vanishing: a waitress missing from a roadside diner and four stories that don't match. It's a Medium case that fits one evening, like The Wolf Feast and The Lighthouse Signal. Every case has tips if you get stuck.

Can I try one before I buy?

Yes. Speak Now is a short free case. You need a free account to play it, no card. Try it free

Can I play on my phone?

Not for a whole case yet. You can read the case file on a phone, but handing evidence in needs a computer, so play on a laptop or desktop. For a group, connect the laptop to the TV.

Is DetectiveOS part of Hunt A Killer?

No. Hunt A Killer is a trademark of its owner, and DetectiveOS is not affiliated with it. We just think its fans will like this too.

ready for the next file?

Eight cases. No waiting for the post.

See all 8 cases →Play a free case

Hunt A Killer is a trademark of its owner. DetectiveOS is not affiliated with Hunt A Killer.

8 mystery casesFrom $7.99 · pay once
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