One, Two, Buckle my Shoe (Hercule Poirot Number 23), Agatha Christie. William Morrow Paperbacks (ISBN: 9780062073778) 2011 (originally published 1940).

Summary: Poirot seeks the murderer of his dentist, found dead not two hours after Poirot visited him.

Like many of us, Hercule Poirot does not like going to the dentist. But his appointment with Dr. Morley goes off uneventfully. Except for complaining of the unexpected absence of Miss Nevill, his assistant, their conversation, as much as was possible, was pleasant. Two hours later, Poirot learn Morley has died, in what was an apparent suicide.

But Poirot is not so sure. Even after the inquest, when evidence came out that his last patient, a Greek man named Amberiotis, died in his hotel room of an overdose of the painkiller Morley used. The authorities believed that Morley killed himself for his mistake. But Poirot, having interacted with him, and talked with others who knew him, isn’t so sure.

For one thing, the telegram calling Miss Nevill away was a decoy. There were several other patients, including successful financier Alistair Blunt, former actress Mabelle Sainsbury Seale (who Poirot briefly encountered), and Amberiotis. Also, an American, Howard Raikes came, and not wanting to wait, left. One other, who did not have an appointment, also came. Frank Carter was Miss Nevill’s fiancé, and not approved of by Dr. Morley. He had come to plead his case with the doctor, including the new job he’d just gotten. Finally, Dr. Reilly, his partner, appears to have a drinking problem, and his practice is not going well.

More strange things happen. For one, Mabelle Sainsbury Seale disappears. A month later, police find a body in the lodgings of a Mrs. Albert Chapman. Mabelle’s clothing is found on the body, but dental records reveal her to be Mrs. Chapman. Both had been patients of Dr. Morley. Then Blunt, who had just survived one assassination attempt where Frank Carter was present, invites Poirot to his estate, to persuade Poirot to search for the missing Mabelle. While they are talking, a shot is fired, but misses Blunt. The gun, a match for the pistol by which Morley died, is at Carter’s feet. Carter’s “job,” as it turns out was as a gardener at the estate.

Things are not looking good for Carter, who is hardly of the most exemplary character. But Poirot comes to think that a trap has been laid, not only for the hapless Carter, but for himself. Carter professes innocence to both crimes, saying he came upon Morley after he was shot. The key, Poirot believes, is finding the “missing Mabelle.”

The title rhyme carries through the titles for each chapter. Poirot, as always, thinks as much as he “detects” and it is a reference to a Psalm that puts him on the trail of the killer. This was Christie at the height of her powers in 1940 in a well-paced mystery with a number of “red herrings.”