To the best of my knowledge, in the Joker Game anime, we are not consistently given information about when the different events shown occur. I do know the following:
- "Joker Game" clearly occurs shortly after the founding of D-Agency in autumn of 1937.
- "XX (Double Cross)" occurs in spring of 1939.
- "Robinson" and "Asia Express" take place in 1939.
- "Double Joker" includes a flashback that takes place six months before the main events. In the flashback, the D-Agency has recently been created; the main events then probably are in 1938.
- The spy in "Miscalculation" had a one-year stay in France planned, starting from June 15, 1939. France was occupied in June 1940, so it seems likely that "Miscalculation" is set in 1940.
- "Pursuit" makes reference to the events of "Robinson", and so must have occurred afterwards.
We also see a character in "Coffin" comment that a behind-the-scenes three-way alliance between Japan, Germany, and Italy has been formed. This restricts the possible dates of the main events of that episode, but I still do not have anything narrow enough for want of sufficient historical knowledge.
I am left without knowing when "City of Temptation", "Pursuit", "Codename: Cerberus", and "Coffin" take place. (It is obvious, for instance, that "City of Temptation" takes place when Shanghai was occupied by the Japanese, but the resulting timeframe is still rather large.) Is there any official information on when the various events happen? If not, can we make any inferences (based on details we see, or details in other adaptations of the same material) to make educated guesses?