Extensive destruction in the Mediterranean Sea caused a significant collapse in 2029. The Earth's crust suffered a sudden loss of vital chemical elements like carbon, gold, molybdenum, cobalt, and oxygen, leading to a 90% decrease in human population in just 60 years. Further investigation revealed that an alternate dimension planet, "Nega Earth," absorbed these elements. In a bid to protect Earth's future, a team of skilled young element hunters was formed, deemed better suited to access "Nega Earth."