Android On Google Play 
Write SQL. Crack cases.
Deadlock Holmes is a free Android game that teaches SQL: you solve noir murder cases by writing real queries against an embedded SQLite database, and the whole thing plays offline.
On Google Play as Deadlock Holmes: Learn SQL
Get it on Google Play
Free to download · In-app purchases · Ads
What Deadlock Holmes is
Deadlock Holmes is a noir detective game where you solve murder mysteries by writing real SQL against an embedded SQLite database. No dialogue trees, no minigames, no hint arrows - SQL is the only investigative tool you get. That constraint is the whole point, and it is what actually teaches you the language.
Every case has a deep suspect pool, so you cannot eyeball a SELECT * and guess. Each decoy fails on a different clue - you have to reason. Accuse the wrong person and you forfeit XP. It costs you.
It is not a quiz app and not flashcards. You write the query yourself, it runs for real, and either the answer is in the result set or it is not. That is why it sticks.
How Deadlock Holmes plays
- 01
Read the case brief - hardboiled 1940s detective voice.
- 02
Open the Workspace and query the evidence tables: phone logs, alibis, ledgers, key-card swipes.
- 03
Queries execute on real SQLite. Real results, real error messages when you get it wrong.
- 04
Pin results to your Notes, check the Schema tab, then name your suspect in Submit.
- 05
Wrong accusation? You forfeit XP.
Key features of Deadlock Holmes
- 01
Hand-authored cases
Grouped into volumes on a difficulty ladder - from single-table SELECT and WHERE up through JOINs, GROUP BY and subqueries.
- 02
Custom SQL keyboard
No fighting autocorrect. Keyword keys, table and column suggestions, JOIN templates, and an in-app SQL guide.
- 03
Progressive hints
Stuck? Hints reveal just enough to get you moving again.
- 04
XP & rank ladder
Progress saves, cases unlock in order, and a case tally sits on your desk.
- 05
Full noir dressing
Cork pinboard, red string, torn paper case files, wax seals, rubber stamps.
- 06
Fully offline
No internet, no account. The whole precinct fits in your pocket.
Deadlock Holmes at a glance
- Platform
- Android
- Availability
- Available on Google Play
- Price
- Free to download
- In-app purchases
- Yes
- Ads
- Yes
- Offline play
- Yes - no internet or account needed
- Players
- Single player
- Content rating
- Everyone
- Languages
- English
- Content
- Hand-authored cases grouped into volumes on a difficulty ladder
- Genre
- Educational / Puzzle
- Developer
- WRTeam Games (WRTeam IT Pvt. Ltd.)
Deadlock Holmes, answered
Do you need to know SQL before playing Deadlock Holmes?
No. The first cases only need a single-table SELECT with a WHERE clause, and the difficulty ladder works up through JOINs, GROUP BY and subqueries as the volumes progress. An in-app SQL guide and progressive hints are there when a case stalls.
Does Deadlock Holmes teach real SQL or a simplified version?
Real SQL. Queries execute against an embedded SQLite database on your device, so you get real result sets and real SQLite error messages when a query is wrong - the same ones you would get outside the game.
How do you solve a case?
You query the evidence tables - phone logs, alibis, ledgers, key-card swipes - pin the rows that matter to your Notes, then name a suspect in the Submit tab. Every case has decoy suspects that each fail on a different clue, so guessing does not work.
What happens if you accuse the wrong suspect?
You forfeit XP. Accusations are not free, which is what stops the game from being solvable by trial and error.
Does Deadlock Holmes work offline?
Yes. There is no account and no internet requirement - the database, the cases and your progress all live on the device.
Is Deadlock Holmes free?
It is free to download on Google Play. It contains ads and in-app purchases, and is rated Everyone.
For people learning SQL who bounced off tutorials - students, career switchers, analysts, devs prepping interviews - and detective-game fans who want something with actual teeth.
Get it on Google Play