Hide My Eyes in the Albert Campion series by Margery Allingham is a repeat US Kindle Countdown deal at $0.99 for about 2 1/2 more days. As with many of Allingham's titles, it has alternate titles - it has also been published as
Tether's End and/or
Ten Were Missing.
link:
https://www.amazon.com/dp/B00LJ118SW