In the past two decades, astronomers have discovered thousands of planets outside our solar system; they believe there are trillions more. If life exists on even a fraction of them, then the cosmos must be teeming with alien species. But what do those aliens look like? How do they feed, reproduce and evolve? This series applies Earth's laws of life to the rest of the galaxy. Using CGI techniques, it combines facts with science fiction and gives a picture of what extraterrestrial life might look like on other planets.