A Coffin for Demetrios by Eric Ambler; Delirium by Laura Restrepo

Excellent psychological thriller. Great detail, interesting characters, and an absorbing plot that builds to a fantastic climax.
Charles Latimer, a mystery writer, learns of the death of a shady man named Demetrios though his acquaintance with a member of the Turkish secret police. In an attempt to impress on the protagonist that real murders and their deeds are less neat and far more senseless than in books, the colonel shares Demetrios' dossier with him, even going so far as honoring a request to see the body down at the morgue.Taken by morbid curiosity, Charles starts off on his own journey to map out Demetrios' sordid dealings, moving from one country to the next, following the trail of crimes. He discovers the various schemes of this very nasty individual and meets the people he worked with along the way.

A very absorbing look at an episode of madness as manifested by Augustina, a rich Colombian woman living with her husband, Aguilar. Aguilar comes back from a business trip to find her in a hotel room experiencing a more protracted and intense delusional episode than she's ever had before. He sets out to find out what caused it.
The book has several viewpoints. One, the husband describes her mental state and the care he and her Aunt Sofi give her, how he goes about dealing with the situation, and a little bit of his history with her. Two, an old friend of Augustina recounts a story  about a bet gone very wrong and an offense against a drug lord that leads up to the event that causes the psychotic break. Three, descriptions of the madness of Augustina's grandfather. Four, Augustina herself telling the story of her family and her relationship with her little brother, Bichi.
Her writing style seems to be influenced by Jose Saramago only she's actually worked with it rather than used it to bludgeon her readers. It flows, lyrically along, sweeping up the reader and leading from one sentence to another.Saramago just puts one sentence after another, one piece of dialogue tacked onto the with no distinction apart from capitalization. Where his style makes his text artificially difficult to read (and incidentally makes trite subject matter and bad characters seem literary) hers plunges the readers into the stream of consciousness of life and delirium. She respects the need for the occasional dialogue tag or description to orient the audience.