In the novel The Clocks, Miss Katherine Martindale is the owner of the Cavendish Secretarial and Typewriting Bureau. Nicknamed “Sandy Cat” by the typists. Miss Martindale used to be the secretary of author Garry Gregson.
It is later revealed that she is the sister of Valerie Bland. She worked with her brother-in-law to murder Duguesclin, and killed Edna Brent.