Nine years after the disastrous Discovery mission, a new expedition made up of Americans and Russians sets out to find the lost ship and search the database of the rogue computer HAL 9000 for something that might explain what happened. The book is, in reality, a continuation of the film more than of the novel. If the previous one showed the rivalry between the United States and the Soviet Union, now the antagonist is China.
Alongside the adventure of the journey and exploration (the descriptions of space are magnificent), this second installment also reflects on immortality, almost always from a materialist and disenchanted point of view (although this perspective is not reiterated in this science fiction work), as well as on feelings and interpersonal relationships. The behavior of HAL 9000 thus appears again: what information the computer has, whether this data shows contradictions, how the computer makes a decision despite these contradictions, etc.