A team of scientists aboard the International Space Station discover a rapidly evolving life form that caused extinction on Mars and now threatens all life on Earth.

Six astronauts aboard the space station study a sample collected from Mars that could provide evidence for extraterrestrial life on the Red Planet. The crew determines that the sample contains a large, single-celled organism - the first example of life beyond Earth. But..things aren't always what they seem. As the crew begins to conduct research, and their methods end up having unintended consequences, the life form proves more intelligent than anyone ever expected.