Superman II (1980) on Netflix

The meta-human heritage of the Last Son Of Krypton is tested as never before when a series of misadventures unlocks in Superman a very human emotion - love. Superman's love for journalist Lois Lane reaches a seemingly impossible peak, but requires the ultimate sacrifice - as the incompatible molecular structure of Kal-El and Lois would gravely complicate the inevitable bearing of children, Kal-El must be purged of his superpower, to live as a mortal. Kal-El, despite the pleas of the spirit of his long-lost mother, willingly agrees, and now a normal human being, consummates his love for Lois - a decision that dooms the Earth as three criminals from Krypton, freed from their extra-dimensional prison, lay waste to the planet in a path of conquest aided by the planet's most arrogant criminal, Lex Luthor, who intends to smoke out Superman for his destruction - unaware as he is of The Man Of Steel's helplessness, a condition that only one last hope can rectify.