In August 2012, a NASA rover named Curiosity touched down inside Mars Gale crater. The rover carried new scientific instruments designed to answer one question: Could Mars have ever been suitable for life? With inside access to the massive team of scientists and engineers responsible for Curiositys on-the-ground experiments, filmmakers were there for the exhilarating moments after the rovers landingand for the spectacular discoveries to come. As we reveal the dynamic new picture of Mars that these explorers are painting, we will consider the deep questions raised by 40 years of roving Mars: How do we define life?