Script Mother Unknown

Karl, a sculptor, escapes WWII to Tangiers (Morocco). One evening, he finds his (3-4 year old) son at his doorstep with a letter: You wanted a son without the mother: here he is. Do not try to find out who I am. X. As the war ends, the boy asks his father to find his mother. There are three possible women, and Kurt goes in search: Naples, Paris, and Avila. This is the first of my father’s three major novels and the only one not adapted into a film. It has been significantly improved (especially regarding content editing, which it initially never received) as it was adapted for cinema and, for the first time, translated into English. I am contemplating working on this book towards a synopsis/scenario, but I need ideas regarding the structure. A straight/traditional timeline is not an option, and I am thinking something "a la Tarantino". Mother Unknown was about to become a movie at Senior's demise, and though there was a script that got lost, I still retain Senior's synopsis. This is Senior’s strongest novel.