In November 1869 the ship Electra sails from Amsterdam.
On board is a young missionary Heinrich Dirks, together with his wife Aganetha, who are supposed to begin a new missionary work on the distant island of Sumatra.
In the southern part of Batak territory, where Islam is advancing rapidly, their task is to found a new mission station and preach the Gospel.
Most of the Batak are still heathen.
They worship the spirits of the dead ( begus ), and are considered to be one of the las.