Synopsis by Bruce Eder
The entire Earth is placed in jeopardy when a huge asteroid -- measuring more than five miles across -- approaches on a collision course. In a last ditch effort to save the planet, and the city of Metropolis, which is right in its projected impact area, Superman (George Reeves) launches himself into space directly at the object and manages to deflect it into a close orbit around the Earth -- but he is nearly destroyed, returning to Earth weakened and shaken up so badly that he can't recall who he is. Suffering from amnesia, he finds his way to the apartment belonging to Clark Kent and collapses while in the shower. He spends the next few days with help from Lois Lane (Noel Neill) and Jimmy Olsen (Jack Larson) trying to get his strength back and remember anything about himself. Meanwhile, Daily Planet editor Perry White (John Hamilton) is increasingly desperate to find Superman, as the asteroid's presence so close to the Earth continues to threaten the safety of the planet. His contact with Superman has always been through Kent, but Kent can't remember who he is or who Superman is, much less how to contact him. Finally, a series of accidents demonstrate to him that he is Superman, and he rushes to confront the new threat to the Earth, even though a second encounter with the asteroid could kill him.