A New Theory about the Origin of Thailand's Language and People. . . Walking the World 2, Book Two of Terrence Kero's ground-breaking trilogy about human migration, tells the story of how five ethnic/linguistic hunter-gatherer clans left Africa some eighty thousand years ago and migrated to the western border of Thailand over the course of many millennia. The novel opens in 2011 at the University of California Berkeley, where Hanna Koskinen is an anthropology graduate student planning to write her PhD thesis on early human migration. When she becomes friends with Leewan Somwan, her next-door neighbor from Thailand, she begins to consider making Thailand the focus of her research, and when she falls in love with Leewan's brother, Chaat, her decision is sealed. Chaat is a brilliant linguist who has developed a theory about the earliest prototypes of the five major Southeast Asian language families, and Hanna thinks she can use his theory, along with human population genetics and age-dated archaeological discoveries, to support the bold argument she wants to make in her thesis: that Thailand was the initial gateway for the first migration of homo sapiens to Southeast Asia. Stories imagining the tragedies and joys of these prehistoric people on their arduous journeys are interspersed with the present-day narrative of the tragedies and joys of the Koskinen and Somwan families, a narrative culminating in dramatic revelations about the early ancestry of the Somwans and the unexpected links that bond humankind.