Start the quest by speaking to Caroline who is located just north of Witchaven. She will tell you about her husband and he son who went to the fishing platform and haven't returned for some time now. You will agree to help find them and bring them back to her. Now speak with Holgart who will be taking you to the fishing platform.
Go speak to Holgart who roams around and ask if you can use his ship. He will tell you about his little dilemma with his ship having holes in it. He needs some swamp paste to fill in the holes. You can either buy this paste from the Khazard General Store or make it on your own. Give the paste to him, and talk to him again to sail to the Fishing Platform.
Finding Kent and Kennith
Once on the platform, head west until you see a little building. Enter it and talk to Bailey to find out where Kennith is. Go to the north-east corner of the platform, and climb up the ladder. Head to the north-west corner then and into another building and talk to Kennith.
He will tell you that his dad went for help days ago. Head back to Holgart, and he will suggest trying to find Kent. You will find him on a deserted island, and he tells you that sea slugs are controlling the minds of the fisherman.
Kent wants you to go back and save Kennith, so return to the platform with Holgart. Head back to the ladder to get to Kennith, but the fishermen will pull you back down when you try to climb it.
Go back and talk to Bailey for suggestions. He will tell you their weakness is heat, and gives you a damp unlit torch. Take the nearby broken glass, then head in the direction of the ladder. Near the ladder, you will find some damp sticks. Use them on the broken glass to dry them, then rub them together to create a flame, and light the torch.
Head up the ladder now, and talk to Kennith. After talking to him, kick the badly repaired wall, and talk to Kennith again. Operate the crane, sending him down to saftey, and return to Witchaven and talk to Caroline.