Description:
Department K didn't tell John Craig why Kaplan was important. That
wasn't his business. His business was to get Kaplan out of Turkey
despite the very hostile attentions of competing intelligence services,
including his own! Very quickly Craig realizes that there is no-one he
can trust on this violence-strewn journey except himself; and that there
are probably no innocent bystanders.
Made into a 1972 movie with Stanley Baker, Geraldine Chaplin, and Donald Pleasance:https://en.wikipedia.org/wiki/Innocent_Bystanders_(film)