Two hundred years in the future, in a fully colonized solar system, police detective Josephus Miller is given the assignment to find a missing young woman, Julie Mao. Joining his task is James Holden, former first officer of an ice freighter who is involved in an incident caused by the tense relationship between Earth, Mars and the Belt. Far from their struggles in space, United Nations executive Chrisjen Avasarala works to prevent war between Earth and Mars. Soon the three find out that the missing woman is connected to a vast conspiracy that threatens all humanity.
In the year 1987, Air Force captain William "Buck" Rogers tests the Ranger 3 spacecraft. His flight was to last only 5 months, but a meteor storm damages his life-support systems, freezing him solid, and casts Ranger 3 into an orbit which returns it to Earth--over 500 years later. Soon after Buck departs, Earth is devastated by a nuclear war caused by a renegade group of U.S. military officers. In 2491, Buck, who has survived due to the freezing, is revived and tries to adjust to life on 25th-century post-nuclear Earth. In the second season, Buck joins the crew of the Searcher, a starship dispatched to locate former Earth colonies in deep space.