''Diabolic Candelabra'' by E. R. Punshon (d. 1956), public domain. The book blends a seemingly impossible murder investigation with labyrinthine puzzles, a wood-dwelling hermit, an animal-whispering girl, and an evil stepfather.
The story kicks off when Bobby Owen's wife, Olive, sets out to find the recipe for some "uncommonly good chocolates". However, this innocent domestic quest plunges the Inspector directly into a web of trouble. The plot prominently revolves around two highly valuable pieces of art and a series of seemingly impossible murders that will test even the cleverest armchair sleuths.
E.R. Punshon's signature discursive writing style is on full display in this novel. Readers can expect a brilliant, character-driven mystery punctuated by his sly wit and social commentary, making it a highly regarded installment in the Golden Age of Detective Fiction.