Emerald Decision by "David Grant" (1980)
Emerald Decision is the second of two novels written by David Grant. Perhaps it wasn't published under the name Craig Thomas as it didn't include any of the recurring characters which he'd established in the first four books. (Or perhaps it's because there isn't an animal in the title!>
In fact we get two books in one. Both stories unfold together and in some places cleverly mirror each other's action. In 1940 an Anglo-Irish spy called McBride is uncovering German U-Boats and agents in the South of Ireland. In 1980 his American son is doing research for his latest in a string of popular history books. Were the Germans preparing to invade Ireland? For both men there are those who would rather the truth remained uncovered.
The book was inspired by the experiences of Craig Thomas' father who served on minesweepers in World War II. certainly the sections of the book describing the minesweeping operations stand out as among his most vivid and memorable passages.
This book remained out of print until 1987 when the publisher Collins started to print Thomas' books starting with Winter Hawk. Their paperback imprint, Fontana, had previously published Emerald Decision so now a revised edition appeared with the name Craig Thomas prominently displayed.
Changes inside mainly involved the changing of the date 'October 1980' to 'October 198-' and references to the 1985 Anglo-Irish agreement were inserted to make things more topical. This required a little rewriting to remove references to Northern Ireland politicians being direclty involved in talks at Leeds castle against a backdrop of IRA violence. Personally I think the original version works best as a reminder of a specific point in recent history.