Superman IV: The Quest for Peace

Superman saves a spaceship of cosmonauts whose ship was thrown off course by debris, then visits his home-town of Smallville as Clark. Now that his adoptive parents have died, Clark has inherited their now-unattended farm. In an empty barn, he uncovers the capsule that brought him to Earth and removes a luminescent green Kryptonian energy module. A recording left by his mother Lara states that its power can be used only once. After refusing to sell the farm to a mall developer, Superman returns to Metropolis, where he stops a runaway subway train after the conductor collapses at the controls.