Mr. Smith got the letter from his dead drop at the market. A week later he passed its contents to Agent Y by blinking in Morse code on the train.
Agent Y etched it on a penny which they dropped at the collection box of the 3rd street church.
Finally, it reaches you hidden in the instructions on a box of oatmeal:
…add boiling water and cover for 5 minutes. I like you, do you want to go get pancakes?
[ ] YES [ ] NO [ ] MAYBE