A Thing

You decide that the ocean would be a fun place to explore, and even if you change your mind later, at least you will still have that cool under water breathing amulet. You go to the local fishing store to purchase a harpoon gun, two thousand years worth of food, state of the art deep sea vision technology, and a new t-shirt with a picture of two really cool sharks on it.

A month later you find the amulet just sitting on the side of the road, and now your adventure can truly begin, but where to start?