A/N: I haven't tried to write something in chapters in a while, so I'm challenging myself this time. It still probably won't follow a typical chapter structure, since it's just... a huge fic that'll be posted in chunks.
And I may yet get frustrated with the chapter format and write all the end in one go eventually. You have been warned.

Have an introduction I guess.

The first glimpse he gets is from Kirk's boat.

The heat of summer is just barely starting to fade into autumn, and the air is still heavy with warm moisture. Mark watches the island as it draws closer–Mushroom Island, they called it, after the three great parasol-like fungi he hid under to escape last week's torrential rain. For all it is covered with apparently undisturbed grass, he can see life in the woods of the new island. He hasn't gone in, this time of year's busy schedule doesn't leave him much time for idle exploration, but he's heard them moving between the trees and under the brush on his short foraging sessions. So he stares ahead when the boat speeds towards the island, tries to catch sight of a rabbit or a boar before they can hide, but what he sees instead is a silhouette on the beach, staring back at them.

"Did you bring anyone in today?"

Kirk looks at him, blinking; Mark stares in confusion for a few seconds before understanding and moving out of the sun's path.

"I didn't–is someone there?"

"I think..."

He looks back towards the island, but the silhouette is gone, and when he sets foot on the beach there are no hints of its presence–the sand looks undisturbed, and the woods are as peaceful as ever.