Charles Fort, the great American Rebel Philosopher, believed that every man had the right to doubt. He aimed his merciless shaft at scientists and religious leaders alike. No dearly cherished doctrine was safe from Fortean criticism simply because it was old and accepted. Fort wanted proof. He wanted more proof than any scientist could give. He demanded to see with his own eyes, to hear with his own ears. Just because a telescope indicated that a certain astronomical fact was very probable was no proof to Fort that it was Fact. He would not have accepted that the earth was 93,000,000 miles from the sun until he had run a measuring chain across the intervening space! There will be men like Charles Fort in every age, on every civilised planet. They will want proof. They will want to see and hear alien races for themselves. They will fly their valiant exploring ships to every corner of the universe. They will live. They will die. They will fail. They will succeed. This is the story of one of their journeys.