A man and his sister discover something sinister in the skies above their California horse ranch, while the owner of a nearby theme park tries to profit fro the mysterious, otherworldly phenomenon.

本剧集将地球生物的规律应用到宇宙的其他地方，融合了科学事实和虚构故事来想象其他星球上的生命。

The six-member crew of the International Space Station is tasked with studying a sample from Mars that may be the first proof of extra-terrestrial life, which proves more intelligent than ever expected.