This instalment is tricky to reflect upon. I'm bestowing three stars because it entails several exciting events that elevate the interest and pace. I like that it is a fresh setting to dig into away from Nancy Drew's 'River Heights' neighbourhood; although I don't know which American state that's in. The desert evokes inspiring terrain and mood-setting history; as does the ranch.
The nocturnal horse does not contribute the spooky atmosphere it should. Nancy clarifies from the start that she predicts a non-spiritual explanation and if folks excuse my blunt plea: I wish more authors would have the balls to actually write in the paranormal! The 1930s, when these volumes began being created, were the height of parlour séances and metaphysical interest. If an author prefers 'rational outcomes', then they should not use paranormal intrigue to entice readers.
It is nice that volume V proclaims the partnership of well-known cousins, 'George & Bess'. However I really liked 'Helen Marsh' and find it ridiculous to cease the consultation of her friendship and skill, because she was slated to marry. Bess being plump and George tomboyish, are a nice variation of body types but cliché digs about Bess being hungry were off-putting. The mystery itself was excellent: old family treasure on an old property and a kidnapped parent were very worthy to investigate. The ranch owners' suggestion that the girls leave was overdone, when the reader knows Nancy is the person who SHOULD handle a mystery.