Orders from High Overseer Campbell is a written note found in Dishonored.
I bid you safety and courage on your expedition.
The assassin Daud and his cultist followers are commonly known as the Whalers, due to the oil worker masks they wear. Beware, for Daud may possess power and resistance beyond expectation. Tread with extreme caution; their infamy is well earned.
They are based inside the Chamber of Commerce building in the ruins of Central Rudshore. All roads to this area have been blocked, with the exception of the elevated rails. Find the rail station in the Rudshore Market.
March carefully, for the cultists undoubtedly employ spies to watch the route.