Island Gambit - International Mission Force, #4

Fourteen-year-old Toby and his sixteen-year-old sister, Amy, are both searching for answers. While Toby delves into the deadly mystery he's uncovered in the wilds near their home in the highlands of Papua New Guinea, Amy searches for a divine purpose beyond her daily routine. When their good friend, Joaquin, comes home on shore leave, he brings a stranger from half a world away who threatens to interrupt both of their quests.
Toby soon discovers that trusting the newcomer may risk exposing his secrets, but for Amy, the question is whether she can trust him with her heart. Catastrophe strikes when a mudslide destroys a village near their home, and ancient customs are twisted by modern motives of greed and violence. Toby and Amy find their quests converging in a life and death struggle where the sacrifice required of those who serve becomes clear.
Will Toby and Amy find that setting aside their personal interests may lead to the answers they sought?