A House Without Boundaries(1972)

Original title: La casa sin fronteras

Daniel is a member of The Organization. He is sent on an assignment to Bilbao to determine what has become of a lad his age, a former member. He takes over the boy's room in an odd rooming house. When he is given the photo of the boy's girlfriend, he is so taken with it that he puts off his quest. The Organization requires him to continue, however, so he tracks her down to a remote fishing village.