The private island, shrouded in secrecy and exclusivity, is likely to be a place of immense power and wealth, controlled by individuals who hold tremendous sway in the world.
The man in question, taken against his will, is likely to be subjected to a variety of challenges designed to test his physical and mental fortitude. These challenges could range from extreme physical labor to mental puzzles and tests of strategy and cunning.
While the idea of being forced into slavery and subjected to such challenges is unsettling, it is also possible that the man could find allies and supporters among the other slaves and workers on the island. It is also possible that he could find a way to turn the tables on his captors, perhaps by forming alliances or gathering information that could be used to his advantage.