I. The 4th Expedition - ethereal and delicate; some of Earth's most desparate refugees finally come into view of Mars. II. Colonization - the Earthmen get to the task of establishing a functioning colony. III. The Human Plague - unfortunately the refugees have brought with them a multitude of viruses and bacteria that eradicate the indigenous Martians. Simultaneously, full on nuclear war has decimated Earth. IV. The Million-Year Picnic - ethereal and delicate once again, but with a twang of regret and foreboding. The last of mankind now struggles to survive on Mars.