The characters seem alive and three-dimensional from the very beginning, which is what kept me reading despite the slow start. James and his friends Lim and Kim are very likable and often just plain fun to read about. In one passage, Lim playfully refers to the group as an exclusive club called the “Im-Crowd,” since all of their names end with “im” (Jim, Lim, Kim). Then, at times when they're lucky enough get together, they continue to joke about it and play on words with the prefix “im.”
The author doesn't disappoint when it comes to the science, either. His descriptions of space elevators, space travel, the conditions on Mars, and the possibilities of extraterrestrial microbial life are exquisite and well researched.
Personally, I was delighted that James didn't stumble upon an ancient Martian city hidden deep beneath the surface. .... What James does find might be more realistic in light of current theory, and might have almost as far-reaching an impact on humanity.
The Mars Imperative is a serious science fiction with excellent character work and dialogue, and a thrilling adventure into the not-so-distant future. It's easy to read and will keep the reader enthralled to the very end.