"Sing the code-phrase" is a mission objective in Freedom Cry in Laying The First Brick
Walkthrough[edit]
From the top of the Slave barracks you have a chance to air assassination the overseer. You can take that option or just jump down, carefully, into the sugarcane field. If he comes to investigate, take him out. Now head to the Northern end of it and interact with the singing Contact. She will point you toward your next contact in the area.
