The murder appeared to be a crime of passion, the killer having left a trail of evidence behind him that even a blind man might have followed.
It was the identity of the victim, not the murderer, that brought Scotland Yard into the case.
No one knew who she was. Or, more correctly perhaps, what name she might have used since 1916. And what had become of the man and the two children who had been with her at the railway station? Were they a figment of the killer's overheated imagination? Or were their bodies yet to be discovered?
The police in Dorset were quite happy to turn the search over to the Yard. And the Yard was very happy indeed to oblige, in the person of Inspector Ian Rutledge.