Honestly I can't rememnber exactly why I rated this book only 2 stars but it must have been a mediocre plot and, I think I recall, not realistic reactions, conversations, etc for its time period setting. ( )

High Treason at the Grand Hotel picks up right where Betrayal at Ravenswick ends. In the second book, Fiona is sent to Paris to once again follow Frederick Fredericks, who is believed to have something to do with British ships being sunk by the Germans. She has been explicitly ordered by her bosses not to don any disguises this time, an order Fiona disregards.

She goes undercover as a bellboy at the Grand Hotel to gain access to Fredericks' room. She also becomes involved with notorious spy Mata Hari, and infamous serial killer Henri Desire Landru. I found Fiona's interaction with actual historical figures added a extra level of interest to the story.

Once again, a countess is murdered (countesses are not safe in Oliver's books), and Fiona finds herself surrounded by agents and double agents, with Fredericks in the middle of the action. Clifford Douglas, who works for British intelligence, pops up again here, and like Fiona, the reader finds him less insufferable in this second book than the first. He starts to grow on you as he and Fiona are becoming a team.

One of my favorite scenes takes place in a library, where Fiona retreats to dig for answers to some of her questions. Even spies know that you can find the answer to anything in the library.

I enjoyed the combination of action, a little romance, humor (Fiona having to lug people's bags all day while undercover as a bellboy), and the interesting facts that Oliver throws in the story (the US made Puerto Rico citizens to open up a new avenue for war recruits, the color mauve was created a chemist looking to extract quinine from coal tar). I look forward to reading more of Fiona Figg's upcoming exploits. ( )

Entertaining spy story set mostly in Paris, 1917. Interesting characters including Mata Hari. Lots of laughs.
I requested and received a temporary free ebook copy from Level Best Books via NetGalley. ( )