Books like The Diamond Mystery #1
Martin Widmark
The Diamond Mystery #1 is 80 pages, about 1 hour 28 minutes at 250 words a minute.
12 books to read next
How long each takes
The Murder of Roger Ackroyd 4.7 h 
Hidden Star 6.5 h 
After the Funeral 4.5 h 
Poirot Investigates 3.5 h 
Murder in Three Acts 4.4 h 
The Big Four 4.1 h 
Stars 9.8 h 
Five Little Pigs 4.4 h 
Death in the Clouds 4.7 h 
Evil Under the Sun 4.1 h 
Peril at End House 4.1 h 
Appointment with Death 4.1 h Bar height shows length. Estimated at 250 words a minute.