Hidden in the Depths

Hidden in the Depths is a treasure hunt quest in The Witcher 3: Wild Hunt.

Walkthrough
This quest starts at the hidden treasure marker located southwest of the village of Harviken, on the Skelligan island of Faroe. The marker leads to a man's corpse. Loot it to obtain a message and a scratched key.

Head into the nearby cave entrance, wade through the water, and dive down into the flooded caverns. Keep swimming along the passage, and eventually you should surface in a fairly large underground chamber. Loot the chest for some random loot to complete this quest.

Bugs

 * The quest completes immediately after reading the letter, without directing you to loot the chest in the cavern. Nevertheless, the journal entry updates to say that the chest has been looted.

Quest objectives

 * Read the letter you found.

Journal entry
''They say one can hardly spit in Skellige without splashing a pirate or a pirate's treasure. Geralt's adventures confirmed the wisdom of this proverb several times over. For example, one day he happened across a letter indicating the location of some hidden plundered booty... When Geralt entered the underground cavern, he had to admit it was an excellent hiding place. Perhaps too excellent, in fact - the treasure mentioned in the letter was still there, and it seemed this Njall fellow had never come to collect it.''