"On Such a Full Sea" is a novel by Chang-rae Lee set in a dystopian future where society is divided into distinct communities. The story follows Fan, a young woman from a working-class enclave called B-Mor, who embarks on a journey to find her missing boyfriend, Reg. As Fan travels through various regions, she encounters different cultures and challenges, revealing the complexities of human relationships and societal structures. The narrative explores themes of identity, belonging, and the impact of environmental changes on society, all while highlighting the resilience of the human spirit.