This work investigates the origins of the Rapa Nui people and the potential for pre-Columbian contact between Polynesia and South America. Thor Heyerdahl, a Norwegian explorer and ethnographer, utilizes his background in experimental archaeology to test the hypothesis that Easter Island was settled by migrants from Peru. He organizes an expedition to conduct excavations and interviews with local inhabitants to uncover evidence of cultural and technological diffusion across the Pacific Ocean.

Experts often note that while Heyerdahl's specific migration theories remain controversial and largely unsupported by modern genetic evidence, the book serves as a significant historical record of mid-century archaeological methods. Readers frequently highlight the narrative accessibility of the text, which balances technical observation with the personal experiences of the expedition team.