Not one of Fletcher's better efforts.
1) The motive for the crime is extremely unlikely. 2) The "flash of insight" that reveals the criminal requires deduction that would challenge Sherlock Holmes on his best day. 3) Some critical loose ends are left unresolved. "My own reasons" and "Never mind why" do not enlighten the reader - and would certainly not satisfy the police.
It is a decent story but at the end of a good mystery there should be a sense of completeness and resolution - not so here.
I give the author credit for coming up with an intriguing plot concept. A 20th century town is thrown intact through time, millions of years into the future, where the citizens find a nearly dead planet earth. Unfortunately the plot and behavior of the characters soon become unrealistic, annoying, and predictable.
Nicely written and thought provoking, highly recommended.
An enjoyable crime novel which, unfortunately, collapses at the ending with a rushed and contrived story line.