Down in the Docks is the seventeenth Mission in Far Cry 3. It begins right where the previous mission left you off. You've just found and retrieved a compass which will help you find an ancient knife sought after by Buck, who has your friend Keith captive. If you can find this knife for Buck, he'll release your friend to you.

Objectives
Go talk to Buck.
Follow the compass to locate the entrance.
Enter the bunker.
Reach the submarine dock.
Find the cave entrance.
Find a way into the Chinese ruins.
Enter the bunker.
Explore the Chinese ruins.
Enter in the temple to find the treasure room.
Find solution to reach the treasure room.
Enter the treasure room.
Pick up the compass.
Find an exit before everything collapses.

Mission Number: 17
Previous Mission: Piece of the Past
Following Mission: The Motherlode
Rewards: 2000 XP