Here There Be Monsters

Here There Be Monsters is a quest in Fallout 4.

Quick walkthrough

 * 1) Go to The Shamrock Taphouse and talk to Donny Kowalski on the dock at the rear of the building. Alternatively, you can swim out to the submarine without even talking to Danny; upon discovering the sub, the quest will begin automatically. The periscope sticks out of the water off the shore from the dock, it's not hard to miss.
 * 2) Just out into the ocean is the Yangtze submarine. Investigate the submarine.
 * 3) Talk to Captain Zao.
 * 4) Get the dampening coil from Saugus Ironworks.
 * 5) Collect the nuclear warhead from the unfired ICBM in the submarine.
 * 6) Talk to Captain Zao.
 * 7) Replace the dampening coils and insert the warhead in to the reactor.

Behind the scenes
The name of the quest is a reference to cartographers often drawing sea monsters on unexplored areas of a map. In many cases, a phrase similar to "here there be monsters," such as the Roman "here are lions" (hic sunt leones), was written on the map as well.

Здесь могут водиться монстры