Actress Norma Rice is found dead on a train, and the letters REX are scrawled in red chalk on her compartment window. It is the third death to occur in a mysterious string of murders and Scotland Yard are compelled to send once again for Paul Temple.

Francis Henry Durbridge was born 25th November 1912 in Hull, England. He was educated at Bradford Grammar School, where he was encouraged to write by his English teacher. He continued to do so while studying English at Birmingham University. After graduating in 1933, he worked for a short time as a stockbroker's clerk before selling a radio play, Promotion, to the BBC at the age of 21.

In 1938, Durbridge created the character Paul Temple, a crime novelist and detective. With Steve Trent, a Fleet Street journalist and later his wife, Temple solved numerous crimes in the glamorous world of the leisured middle classes, first on radio, then in films and, from 1969 to 1971, in a television series. In addition to the Paul Temple series, Durbridge wrote other mysteries for radio and television, many of which were also produced for German and Italian television and radio.
Durbridge also forged a successful career as a writer for the stage with seven plays, the last of which, Sweet Revenge, was written in 1991. He also wrote 43 novels, many of which were adapted from his scripts, sometimes with the help of others.

Durbridge married Norah Lawley in 1940, they had two sons. He died at his home in Barnes, aged 85 on 11th April 1998.