Address Unknown is a very short epistolary novel by Kathrine Kressmann Taylor which was published in 1938 and is set in 1933. It consists of a series of 54 letters between two friends, a Jewish art dealer named Max living in San Francisco and his Caucasian friend and business partner named Martin who has moved back to Germany. At first all is well, but as Hitler rises in power and Martin becomes increasingly fond of Nazi ideology, the friendship disintegrates, with tragic consequences for both.
- Ain't Too Proud to Beg: In his final letter to Max, Martin begs for Max to abandon his scheme and stop writing him. Max refuses.
- Murder by Inaction: How Martin lets Max's sister die. She is fleeing the Nazis and arrives at his house seeking shelter, but he refuses to allow her access. She is shot by the Nazis shortly thereafter.
- Please Shoot the Messenger: An unusual example in that Max's final letters to Martin do not explicitly state anything threatening or even unpleasant, but because they're so oddly written and virtually scream 'coded message here', the Nazis interpret that as Martin secretly communicating via coded message with a Jewish spy... and so they have him taken away.
- Revenge: Max's motive after Martin betrays his sister.
- Title Drop: 'Address Unknown' is used to return Max's final letter to Martin, after Martin has been arrested.
- You Are a Credit to Your Race: After spending a short amount of time in Nazi Germany, Martin tells Max this, saying their friendship was more in spite of Max's Jewishness than because of it.