Details
Beauregard is a complicated character. He desires wealth because it will bring him power over people whom he believes look down on him. He is born in Havanna, the illegitimate son of an English sea captain and a Spanish woman. Known first as Martin of Carbonear, he is educated by Jesuits and studies chemistry, which he ultimately uses to produce poisons. He gains access to a minor part of the treasure (although not the main hoard) and uses the money to build a house and to study medicine. He is now takes on the name of Dr Beauregard and enters cultured society, using his skills as a poisoner to dispatch other treasure hunters. At the end of the novel he dies by taking his own poison.
For more details of Beauregard, see the article ‘Three Studies in Evil’ and also ‘Chronology of Evil’.