July 1936. Toronto is in the grip of a deadly heat wave. Horses are dropping in the street. Charlotte Frayne is the junior associate in a two-person private-investigation firm owned by T. Gilmore.

Anti-Semitism and murder in "Toronto the Good" in the depths of the Great Depression provide the historical background for this satisfying mystery. The fabric of the City of Toronto is as fully realized in Heat Wave as it is in all the Detective Murdoch books.

A hate-letter is delivered to Charlotte's boss, who leaves the matter in Charlotte's hands to investigate. On the same day, Hilliard Taylor, a First World War veteran who, together with three other former prisoners-of-war, operates the Paradise Caf , seeks the firm's assistance in uncovering what he believes is the systematic embezzlement of the Caf . These two events, seemingly unrelated, come together and bring to life characters as real to the reader as those of the Detective Murdoch series.

The first book in the Paradise Caf series, featuring Charlotte Frayne, Heat Wave promises fans of Maureen Jennings's mysteries the beginning of a long and enjoyable relationship.