Inspector French once again goes to extraordinary lengths to follow leads and clues which help him unravel the mystery. While the explanations of how many knots a launch can travel in xx hours and the required amount of fuel (including paraffin, assuming for cooking?) border on TMI, the writing carries you along. Not a great deal happens "in the Channel," except French's constant crossing of it to investigate the case. Most of the story involves French talking with bank managers, other policemen and various people only mildly involved. Still, it's an ok example of Crofts style and golden age mysteries in general.
A new republished novel from 1931. Inspector French is called in to solve the mystery of a boat floating in the English Channel with two dead bodies on it. Was it murder and somehow the murderer escaped? Was it murder suicide - but where was the gun? Was there any motive? Further investigation reveals embezzlement where the men worked and more suspects are drawn into French's nets. It is a real puzzle as each suspect in turn shows up dead and therefore unable to be the murderer. A very nice read.