A scientist's assistant uses a time machine to travel to the past in order to find a pirate's treasure and get rich. While in the past he is attacked by the pirates, and unknowingly kills one of his own ancestors, erasing his own existence.
A short child mocked for his height takes comfort from his one friend and his love of airplanes. He is rejected by the air force because of his height, but when his friend designs an experimental rocket that can only be piloted by a short man he becomes the first man on Mars.