One summer afternoon, a ten-year-old boy finds a forgotten trove of postcards. To solve their mystery, he journeys to their postmarked city in search of the person who sent them.

Denmark, 2014. A former police officer asks Carl Mørck, head of Department Q, to find out who brutally killed his young twins in 1994. Although a local inhabitant confessed and was convicted of murder, Carl and his partner Assad soon realize that there is something in the case resolution that is terribly wrong.

A nameless ronin, or samurai with no master, enters a small village in feudal Japan where two rival businessmen are struggling for control of the local gambling trade. Taking the name Sanjuro Kuwabatake, the ronin convinces both silk merchant Tazaemon and sake merchant Tokuemon to hire him as a personal bodyguard, then artfully sets in motion a full-scale gang war between the two ambitious and unscrupulous men.

Two years have passed. After missing their separation, the Leroy seem perfectly successful in their divorce. But the appearance of two new lovers in the life of Vincent and Florence will set fire to the powders. The match between the former spouses resumes.