Lord Peter Wimsey - Strong Poison

The novel opens with mystery author Harriet Vane on
trial for the murder of her former lover, Phillip Boyes: a writer
with strong views on atheism, anarchy, and free love.
Publicly professing to disapprove of marriage, he had persuaded a
reluctant Harriet to live with him, only to renounce his
principles a year later and to propose. Harriet, outraged at
being deceived, had broken off the relationship.


Following the separation, the former couple had met occasionally,
and the evidence at trial pointed to Boyes suffering from
repeated bouts of gastric illness at around the time that Harriet
was buying poisons under assumed names, to demonstrate – so she
said – a plot point of her novel then in progress.


Returning from a holiday in North Wales in better
health, Boyes had dined with his cousin, the solicitor Norman
Urquhart, before going to Harriet's flat to discuss
reconciliation, where he had accepted a cup of coffee. That night
he was taken fatally ill, apparently with gastritis. Foul play
was eventually suspected, and a post-mortem revealed that Boyes
had died from acute arsenic poisoning. Apart from Harriet's
coffee and the evening meal with his cousin (in which every item
had been shared by two or more people), the victim appeared to
have taken nothing else that evening.


The trial results in a hung jury. As a unanimous verdict is
required, the judge orders a re-trial. Lord Peter
Wimsey visits Harriet in prison, declares his conviction of
her innocence and promises to catch the real murderer. Wimsey
also announces that he wishes to marry her, a suggestion that
Harriet politely but firmly declines.


Working against time before the new trial, Wimsey first explores
the possibility that Boyes killed himself. Wimsey's friend,
Detective Inspector Charles Parker, disproves that theory.
The rich great-aunt of the cousins Urquhart and Boyes, Rosanna
Wrayburn, is old and senile, and according to Urquhart (who is
acting as her family solicitor) when she dies most of her fortune
will pass to him, with very little going to Boyes. Wimsey
suspects that to be a lie, and sends his enquiry agent Miss
Climpson to get hold of Rosanna's original will, which she
does in a comic scene exposing the practices of
fraudulent mediums. The will in fact names Boyes as
principal beneficiary.


Wimsey plants a spy, Miss Joan Murchison, in Urquhart's office
where she finds a hidden packet of arsenic. She also discovers
that Urquhart had abused his position as Rosanna's
solicitor, embezzled her investments, then lost the
money on the stock market. Urquhart recognised that he would
face inevitable exposure should Rosanna die and Boyes claim his
inheritance. However, Boyes was unaware of the will's contents
and Urquhart reasoned that if Boyes were to die first, nobody
could challenge him as sole remaining beneficiary, and his fraud
would not be revealed.


After perusing A.E. Housman's A Shropshire Lad (in
which the poet likens the reading of serious poetry to King
Mithridates' self-immunization against poisons) Wimsey
suddenly understands what had happened: Urquhart had administered
the arsenic in an omelette which Boyes himself had
cooked. Although Boyes and Urquhart had shared the dish, the
latter had been unaffected as he had carefully built up his own
immunity beforehand by taking small doses of the poison over a
long period. Wimsey tricks Urquhart into an admission before
witnesses.