First published in 1941, this is the third book in Helen McCloy’s Dr Basil Willing mystery series. Although I’ve been reading the books in order so far, it’s really not necessary and you could start anywhere. I think the first one, Dance of Death, is still my favourite but this one comes close.

The Deadly Truth begins with biochemist Roger Slater being visited in his laboratory by the glamorous Claudia Bethune and telling her about a new drug he is developing: a ‘truth serum’ based on scopolamine. After Claudia departs, Roger discovers that one of the tubes containing the drug has disappeared; aware of Claudia’s love of practical jokes and of the drug’s dangerous properties, he sets off in pursuit but, by the time he catches up with her, it’s too late. Guests are arriving at Claudia’s house for a dinner party – and are about to be served a very special cocktail.

Later that night, Dr Basil Willing, who is renting a beach hut on Claudia’s land, thinks he can see flames through the window of the Bethunes’ house and decides to investigate. It turns out there is no fire, but what he does find inside the house is just as shocking – Claudia, slumped at the table, strangled by her own emerald necklace. As the details of the dinner party begin to emerge, Basil learns that, having had their drinks spiked with the truth serum, each guest had revealed truths about themselves that they would have preferred to keep secret. Now that the effects of the drug have worn off, can Basil separate the truth from the lies and identify the murderer?

Helen McCloy’s novels all have such unusual and intriguing plots! They may seem far-fetched and unlikely at first, but really the murder in each one is just a starting point for McCloy to introduce some fascinating psychological and scientific themes and ideas; in this book, as well as the discussions of truth and lies, there’s also an interesting exploration of sound and deafness. As a New York psychiatrist, Basil Willing solves the crimes through his understanding of the human mind, looking at personalities and motives rather than spending too much time on technicalities such as alibis, and this is the kind of mystery novel I prefer. Basil does have some specialist knowledge which plays an important part in the solution of this particular mystery, but even without this knowledge the clues are there for an observant reader to pick up on. Unfortunately, I was not observant enough and allowed the red herrings McCloy drops into the story to lead me away from the correct suspect!

I think Helen McCloy is one of the best of the ‘forgotten’ crime authors I’ve discovered recently. She also seems to have been quite prolific; there are ten other Basil Willing novels and lots of standalones, so I’m looking forward to reading more of her work.

Thanks to Agora Books for providing a copy of this book for review via NetGalley.