Poison Unknown

"They represent an accumulation of knowledge about poisons it would be hard to find in a single building anywhere else..."

Professor Charles Roseland is the head of the Juliot Research Centre, a small chemical research institute for newly-qualified scientists. One Friday evening, Roseland leaves to attend a scientific gathering in London. On the following Monday, he is discovered dead in his laboratory at the Research Centre. Initially, it seems that Roseland died of a weak heart, but the local police soon uncover the presence of an ex-spy, and the possibilty that the professor was working on an experimental poison gas at the time of his death. It is up to Inspector McCleod of Scotland Yard to determine which of the professor's colleagues had the motive and opportunity to murder him. But when her fiance is suspected of the crime, Roseland's daughter takes her own steps to determine the identity of her father's killer...

Originally published in 1939 this is a vintage murder mystery from the golden age of crime fiction.

Dettagli