E.C. Bentley wrote Trent’s Last Case as a reaction against the artificial type of detective stories popular in the early 1900’s which portrayed detectives as almost superhuman. He believed it was possible to have a detective who was recognisable as a human being with human emotions and not someone who was a perfect reasoning machine, à la Sherlock Holmes.
Bentley’s detective, Philip Trent, is an affable young man, an artist with a literary bent, and a penchant for solving crime cases. He becomes involved in the murder case of a very wealthy man whose life had been lived in the service of greed.

“When the scheming, indomitable brain of Sigsbee Manderson was scattered by a shot from an unknown hand, (the) world lost nothing worth a single tear; it gained something memorable in a harsh reminder of the vanity of such wealth as this dead man had piled up — without making one loyal friend to mourn him, without doing an act that could help his memory to the least honour.”

Trent ‘solves’ the crime through circumstantial evidence but it leaves him in a terrible predicament and he decides not to deliver his findings to the police.
I won’t give any more details except to say that Trent is faced in the end by the ‘impotence of human reason’ and swears he will never touch a crime-mystery again.

‘…as a rule it is in the task of penetrating to the spiritual truth that the administration of justice breaks down. Sometimes that truth is deliberately concealed, as in Manderson’s case.’

The spiritual truth referred to above was Manderson’s ‘insane depth of jealous hatred.’

Bentley’s characters discuss a famous Scottish case, the Sandyford Place murder, where an innocent woman was accused and barely escaped hanging because the ‘spiritual truth’ of James Fleming, an old man who accused the woman, was not discerned.

”Even a commonplace old dotard like Fleming can be an unfathomable mystery to all the rest of the human race,” said Trent, ”and most of all in a court of justice. The law certainly does not shine when it comes to a case requiring much delicacy of perception.”

Some favourite passages:

‘To react against fear had become a fixed moral habit with him.’

‘One felt in the man a complete absence of the sympathetic faculty.’

A description of Philip Trent: ”Aged in his early thirties; long, loosely built; a high-boned quixotic face, pleasant smile; rough tweed clothes, hair and short moustache tolerably untidy.”

The introduction in the Dover Mystery Classic says that E.C. Bentley (1875-1956) was a journalist and a humorist who wrote for Punch. He was a member of staff of the London Daily News and is still remembered for having invented the ‘clerihew:’

Louis Quatorze
Had a penchant for wars.
He sent Turenne to the Palatinate
With instructions to flatten it.

Trent’s Last Case was a refreshing murder mystery with a very likeable protagonist. Bentley’s writing is probably closer to Dorothy Sayers’ more literary style than Agatha Christie’s. He was a good friend of G.K. Chesterton, to whom he dedicated this book.

The book is available free at Gutenberg.