* You may be thinking of a different title. Peter Robinson has written many novels, including the Inspector Banks series. Perhaps you are thinking of another title in that series or a standalone novel.
* "Aftermath" may be part of a different series. Perhaps there is another author who has written a novel titled "Aftermath."
* You may be misremembering the title. Double-check the title and the author's name to ensure it's correct.
To find the ISBN of a Peter Robinson novel, you can search online databases like:
* Amazon: Type the title and author in the search bar.
* Goodreads: Search by title and author.
* WorldCat: A global library catalog.
Please provide more information about the book you are looking for, and I can help you find the ISBN.