The Arrival DLC, Far Harbor Quest

1. Talk to Brooks

Chase is concerned about a synth who was supposed to arrive at Acadia, but hasn't shown up yet. She sent me to Far Harbor to ask Brooks if he's seen the missing synth.

2. Find the Missing Synth

Chase asked me to find a synth that went missing on the way to Acadia. Brooks in Far Harbor told me that the synth headed south along the road out of town.

Find a ruined house with a blood trail inside. Examine it.

3. Follow the Trail of Blood

Chase asked me to find a synth that went missing on the way to Acadia. I followed the directions that Brooks gave me and found what looks like the site of a violent struggle, with a trail of blood leading deeper into the Fog.

4. Investigate the House

Chase asked me to find a synth that went missing on the way to Acadia. My search led me to the scene of a violent struggle, with a trail of blood that I followed to a ruined house occupied by Trappers.

Talk to trapper. You can try to finish it peacefully (charisma check, trapper will give you Missing Synth's Head) or kill all trapers in the house and loot Missing Synth's Head from the body.

5. Return to Chase

Chase asked me to find a synth that went missing on the way to Acadia. I discovered that the synth was captured and killed by cannibal Trappers.

6. Quest completed

Chase asked me to look into the disappearance of a synth who was supposed to arrive in Acadia, but never did. I discovered that the synth was ambushed and killed by cannibal Trappers.

As a reward you will receive 200 caps and a weapon.