Ultimately more utopian than dystopian, the story focuses on egalitarian, sociological, and scientific advances made on Mars, while Earth suffers from overpopulation and ecological disaster.
The mission is a joint American–Russian undertaking, and seventy of the First Hundred are drawn from these countries (except, for example, Michel Duval, a French psychologist assigned to observe their behavior).
Additional steps are taken to connect Mars more closely with Earth, including the insertion of an areosynchronous asteroid "Clarke" to which a space elevator cable is tethered.
He is to some extent joined in this position by John Boone, famous as the "First Man on Mars" from a preceding expedition and rival to Frank Chalmers, the technical leader of the American contingent.
As UNOMA's power erodes, the Mars treaty is renegotiated in a move led by Frank Chalmers; the outcome is impressive but proves short-lived as the transnats find ways around it through loop-holes.
Things get worse as the nations of Earth start to clash over limited resources, expanding debt, and population growth as well as restrictions on access to a new longevity treatment developed by Martian scientists—one that holds the promise of lifespans into the hundreds of years.
In 2061, with Boone dead and exploding immigration threatening the fabric of Martian society, Bogdanov launches a revolution against what many now view as occupying transnat troops operating only loosely under an UNOMA rubber-stamp approval.
Initially successful, the revolution proves infeasible on the basis of both a greater-than-expected willingness of the Earth troops to use violence and the extreme vulnerability of life on a planet without a habitable atmosphere.
(One exception is Phyllis Boyle, who has allied herself with the transnats; she is on Clarke when the space elevator cable is cut and sent flying out of orbit to a fate unknown by the conclusion of the book.)
The clash over resources on Earth breaks out into a full-blown world war leaving hundreds of millions dead, but cease-fire arrangements are reached when the transnats flee to the safety of the developed nations, which use their huge militaries to restore order, forming police-states.
In the meantime, the remaining First Hundred —including Russell, Clayborne, Toitovna, and Cherneshevsky— settle into life in Hiroko Ai's refuge called Zygote, hidden under the Martian south pole.
Melting ice causes the top of the dome of Hiroko Ai's base under the south pole to collapse, forcing the survivors to escape into a (less literal) underground organization known as the Demimonde.
Preparations are made for a second revolution beginning in the 2120s, from converting moholes to missiles silos or hidden bases, sabotaging orbital mirrors, to propelling Deimos out of Mars' gravity well and out into deep space so it could never be used as a weapons platform as Phobos was.
The newly evolving Martian biosphere is described at great length and with more profound changes mostly aimed at warming up the surface of Mars to the brink of making it habitable, from continent-sized orbital mirrors, another space elevator built (using another anchored asteroid that is dubbed "New Clarke"), to melting the northern polar ice cap, and digging moholes deep enough to form volcanoes.
With this, control of Mars is finally wrested away from Earth with minimal loss of life, leaving the weary survivors hopeful about the prospects of their newfound political autonomy.
Blue Mars takes its title from the stage of terraforming that has allowed atmospheric pressure and temperature to increase so that liquid water can exist on the planet's surface, forming rivers and seas.
As Earth is heavily flooded by the sudden melting of the Antarctic ice cap, the once mighty metanats are brought to their knees; as the Praxis Corporation paves a new way of "democratic businesses".
However, when Sax witnesses Ann collapse into a coma during an attempt to demonstrate to her the beauty of the terraformed world, he arranges for her to be resuscitated and to be treated with the longevity treatment, both against her will.
Most common is the event that comes to be known as the "quick decline", where a person of extremely advanced age and in apparently good health suffers a sudden fatal heart arrhythmia and dies abruptly.
Russell speculates that Michel's quick decline was brought on by the shock of seeing Maya fail to remember Frank Chalmers (who was killed while escaping security forces in the first revolution) upon looking at a treasured photo of him on her refrigerator.
He and Ann Clayborne finally recall that they had been in love prior to leaving Earth the very first time, but both had been too socially inept and nervous about their chances for selection for the Mars voyage to reveal this to each other.
In Robinson's future history, the metanational corporations become similar to nation-states in some respects, while continually attempting to take over competitors in order to become the sole controller of the interplanetary market.
Genetic engineering (GE) is first mentioned in Red Mars; it takes off when Sax creates an alga to withstand the harsh Martian temperature and convert its atmosphere into breathable air.
By Blue Mars, GE is commonly being done on humans, willingly, to help them better adapt to the new worlds; to breathe thinner air (e.g. Russell), or to see better in the dimmer light of the outer planets.
The books also speculate on the colonization of other planets and moons in the Solar System, and include descriptions of settlements or terraforming efforts on Callisto, Mercury, Titania, Miranda and Venus.
In the final chapters of Red Mars, Chalmers flees with Toitovna and other members of the First Hundred to join the hidden colonists at the polar ice cap but dies along the way when he is caught outside their vehicle during an aquifer flood in Valles Marineris.
In retaliation for Bogdanov's murder, she activates his hidden weapon system, built into Phobos, which causes the entire moon (a UNOMA/transnational military base) to decelerate in orbit and destructively aerobrake in Mars' atmosphere, utterly destroying it.
A mechanical engineer with anarchist leanings, possibly based on the Russian Machist, Alexander Bogdanov (the character's ancestor) and Arkady Strugatsky, he is regarded by many other members of the First Hundred, particularly Boyle, as a troublemaker.
A Japanese expert on biology, agriculture, and ecological systems, it was Ai who smuggled Desmond "Coyote" Hawkins onto the Ares (the two were friends and lovers as students in London).
The Mars trilogy screen production rights were held by James Cameron in the late 1990s,[8] who conceived a five-hour miniseries to be directed by Martha Coolidge,[9] but he subsequently passed on the option.