Goku has finally returned to Earth. After he lands, the mysterious stranger named Trunks asks to speak with him in private. During this conversation, Goku( and Piccolo) learn from Trunks that he has come from the future to warn them about a coming danger of monster androids (cyborgs) that kill almost everyone. He tells Goku that shortly beforehand he will die of heart failure and he has also brought medicine to ensure Goku can be there to confront them. There are also some surprising revelations about Trunks heritage