Do aliens exist? What do we do if we encounter them? SETI insiders, NASA astronomers, religious leaders, astrophysicist, sci-fi writers and Carl Sagan's own son unite to answer these questions, revealing SETI's decades-long quest to convert science fiction into science fact. Their fascinating insights, along with possible scenarios of what first contact might look like, create a riveting blend of suspense, intrigue and horror. The series showcases the extraordinary scientists who are currently grappling with extraordinary questions about alien life including: what will aliens really look like? How will they sound? What might their worlds look like? And, of course, will they come in peace?

Aliens: The Definitive Guide takes viewers to stunning, remote locations on Earth as well as elsewhere in the universe to investigate whether alien life exists.

The Message
The Arrival
The Invasion
The Offspring