Cain's Jawbone is a murder mystery puzzle written by Edward Powys Mathers under the pseudonym "Torquemada". The puzzle was first published in 1934 as part of The Torquemada Puzzle Book. Cain's Jawbone has been described as "one of the hardest and most beguiling word puzzles ever published.Six murders. One hundred pages. Million of possible combinations, but only one is correct. The pages of this e-book have been published an entirely haphazard order, but is possible to sort them into the only correct order, revealing six murder victims and they respective murderers. In 2022 only three puzzles have ever solved.