Fooled into thinking this is a puzzle style whodunit the reader soon discovers he has instead picked up a crime thriller with the author's primary interest being the criminal's behavior and not the detective skills of the sleuthing protagonists. In reality Marle is a master criminal and master of disguise, with a small army of local crooks and thugs at his command. He is Gregory Marle, a seemingly kindly bookseller who is watching over his pretty ward Pamela Fayne. We learn who he is well before the half way mark. While the story seems to be presented as a typical whodunit it is not Grierson's intention to withhold the identity of the killer until the final pages.

Later in the book Sims will do some detection of his own that follows this pattern: he sees an object, examines it cursorily, then pockets it intending to discuss it with Wells when Grierson sees fit to reveal it to the reader. He tells Sims he knows the murderer and the method based on these three things, but is not sure of the motive. It takes the form of lectures and in one single chapter Wells discusses his findings with Sims based on meeting Gregory Marle, handing him his walking stick after Marle drops it on the floor, and noticing a tiny pinprick in the neck of the corpse. The detection here is not fair play at all. This is an intriguing start, but Grierson almost immediately dispenses with all the mystery in a matter of pages. Wells is quick to mention that this 'smiling death' is often associated in cases of tetanus and some strychnine poisonings. All the victims were wealthy, all bore the risus sardonicus on their faces.

Sims explains that the body may be one of many in a string of unexplained deaths originally attributed to heart failure and dismissed that date back to 1908.

A dead man is found in Tottenham Court Road with a strange smile-like expression on his face. This is the sixth book featuring series character Professor Wells, a expert in chemistry, friend and consultant of Inspector Sims who team up to solve baffling crimes over the course of twelve novels and one collection of short stories. I saw a lot of Wallace in The Smiling Death (1927), a book that begins as a detective novel but quickly turns into a crime thriller with a typical Napoleon of Crime matching wits with a dogged police inspector and his expert sleuth companion. His thrillers were less concerned with the fair play detective puzzles and focused instead on the behavior of the criminals, particularly the special brand of master criminal ( Silinski, White Face, The Twister) and criminal syndicates ( The Fellowship of the Frog, The Green Ribbon, The Crimson Circle) that make up the bulk of his work. Edgar Wallace seemed to have a great influence on many of the crime writers in 1920s England.

Yokomizo seishi il detective kindaichi