Surprisingly good. with some unsurprising character types, the unfeeling boss, the meek woman engineer, the stalwart crew members,nerds, etc. I am an astronomy and physics buff and would like to know the basis for some of the science of the prime elements of this movie, but having said all that, it is highly entertaining suspense with unbelievable special effects, particularly the martian landscape. I was touched by the reverence for "simple" plant life.