A group of teenagers in San Francisco discover a nest of homicidal monsters living in a tower of the Golden Gate Bridge, but when they try to tell authorities, no one believes them.

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. Written by ElDiomedes