A priceless diamond was stolen from a locked museum display case. The security guard swore he never left his post, but security footage showed him walking away for two minutes. When he returned, the glass was intact, the lock unpicked, and the diamond gone. How did the thief get it?
He replaced it with a fake beforehand
The thief didn't steal it while the guard was away; the theft happened earlier. The guard's short absence was just a distraction to delay the discovery.
About this riddle
Detective riddles are tiny mysteries. Look for the detail in the story that does not fit; it is usually the clue that solves the case.
Difficulty: Easy. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
More detective riddles
At 3 AM, a frantic hotel manager called the police to report a jewel heist in room 402. Detective Marsh arrived, interviewed the guest who claimed she was asleep when the thief broke in, and immediately arrested her for filing a false report. The guest was wearing heavy winter pajamas, a thick wool beanie, and thick mittens. Why did Marsh arrest her?
The red heart is bigger than the pink heart, and the pink heart is bigger than the white heart. Which heart is the biggest?
At a dinner party, the host was poisoned with cyanide slipped into his wine glass. Four guests had access: the butler, the chef, the wife, and the business partner. The wife claimed she was pouring tea; the chef claimed he was testing soup; the business partner claimed he was checking his watch; the butler claimed he was dusting the chandelier. Detective Hayes arrested one of them instantly. Who and why?
The famous painting 'Midnight Whisper' was cut out of its frame during a museum gala. Three suspects were questioned. Arthur said he was in the garden smoking a cigar. Beatrice said she was in the basement checking the fuse box because all the lights went out. Charles said he was looking at a sculpture in the east wing. The detective arrested the real thief instantly. Who was it and why?
Inspector Vance found the victim slumped over a desk with a quill in hand. On the blotter, the victim had meticulously written: 'January, February, March, April, May.' Vance smiled and immediately arrested the victim's business partner, who claimed to have been out of town all spring. How did Vance know the partner was lying?
A security guard reported that an intruder smashed the front glass window of a jewelry store from the *inside* to escape with a tray of diamonds. Detective Sterling inspected the shattered glass fragments scattered entirely across the sidewalk outside and arrested the guard on the spot. What gave the guard away?