A Gathering of Saints (1996)

Christopher Hyde's thriller, published by Pocket Books in 1996, is set in London in the autumn of 1940, as the Blitz begins. Detective Inspector Morris Black of Scotland Yard hunts a methodical killer called Queer Jack and is drawn into Churchill's Magic Circle, which fears that the killer knows the Ultra secret, while a German agent known as The Doctor hunts the same man. (Open Library)

Watches

Rolex Oyster Perpetual: Dr. Charles Tennant, in the uniform of a captain in the Royal Army Medical Corps, evaluates captured German agents for Masterman's Double Cross section of MI5 (pp. 23 to 24). His watch is one of his few affectations: a Rolex Oyster Perpetual with a military-style wire-mesh cage over the crystal and a black lizardskin strap. By the river he unstraps it and turns its outer bezel to time a wireless transmission to Heydrich's listening post in Hamburg (p. 115); he consults it again to reckon the tides at Sheerness (p. 371). The text names the Oyster Perpetual; no reference is given, and the turning bezel is the novel's detail.

Source text: The timepiece was one of his few affectations, a Rolex Oyster Perpetual with a military-style wire-mesh cage over the crystal and a black, lizardskin strap. (Christopher Hyde, A Gathering of Saints, scan cataloged as Pocket Books, 1996, p. 91; Internet Archive scan OCR)