Blessing of the Sea follows the life of Shim Chung-yi, a woman born with the extraordinary ability of absolute color perception. Despite her unique gift, she struggles with the mystery of her past and the circumstances surrounding her birth. Her life takes a dramatic turn when she crosses paths with Ma Poong-do, a pianist who suffers from a condition that makes the world appear in black and white. As the two navigate their complicated lives, they become entangled in a web of corporate greed, family secrets, and long-standing grudges involving the J-Group conglomerate. The series explores themes of healing, destiny, and the search for truth as Chung-yi attempts to uncover the secrets of her biological parents while helping Poong-do rediscover the vibrant colors of his own life.