“One Ring to rule them all, One Ring to find them, One Ring to bring them all and in the darkness bind them.”
In ancient times the Rings of Power were crafted by the Elven-smiths, and Sauron, the Dark Lord, forged the One Ring, filling it with his own power so that he could rule all others. But the One Ring was taken from him, and though he sought it throughout Middle-earth, it remained lost to him and the world.
After many ages, it fell by chance into the hands of a hobbit- and Sauron wants it back.