Riviera Gold is the latest (2020) in Laurie R King’s excellent IMO Mary Russell/Sherlock Holmes series – at least until a new title comes out in June of this year. It has dropped to $2.99 at Kindle US, which is a pretty nice price for a most-recent-in-series.
Also, if you want to try the first book in the series, The Beekeeper’s Apprentice, it was on sale in the US and UK a while back. Sadly, it has gone off sale in the US (now priced at $11.99, which is absurd for a backlist title that is almost two decades old), but is still on sale in the UK for £1.89, if you are lucky enough to live or travel there. Info in this previous post.