Case 15: The A.B.C. Murders

A serial killer strikes in alphabetical order: Alice Ascher in Andover, Betty Barnard in Bexhill, and Sir Carmichael Clarke in Churston. Each victim is found with an ABC Railway Guide beside them. Poirot and the police hunt for the man who calls himself "A.B.C."—but the pattern may be a disguise for a single, calculated murder.

Your mission: Use SQL to meet everyone connected to the case, see where each murder happened, find who was wrongly accused, who stood to gain from the third victim's death, and reveal who committed the A.B.C. murders.

About this case

Based on The A.B.C. Murders (Agatha Christie, 1935). A mysterious killer strikes alphabetically: Alice Ascher in Andover, Betty Barnard in Bexhill, Sir Carmichael Clarke in Churston. Each time, an ABC Railway Guide is left at the scene. But is the pattern genuine, or is someone using it to hide a single calculated murder?

What you'll practise

This advanced case demands expert-level SQL analysis:

WHERE with complex multi-town filtering — to track murders across geographic regions
ORDER BY — to build precise chronological analysis across three separate locations
Pattern recognition — identifying whether murders follow a genuine pattern or a false one
Motive analysis — determining who gained the most from the third murder

The database

You'll query the suspect_info table, tracking each victim's connections, financial status, suspects in each town, and the relationships between seemingly unconnected murders.

Difficulty

Advanced. Requires sophisticated pattern recognition and the ability to think through misdirection. The key is realizing that patterns are not always what they appear to be.