This collection of award winning science fiction includes a story that was a finalist for the Hugo Awards and one that was voted one of the 10 greatest science fiction stories to appear during the 1990s. In the title piece, geologist Andrew Mutton has obtained an intelligent mining robot and downloaded the memories of his deceased mentor into the robot's electronic brain. Together, man and robot undertake a project to bore through the crust and mantle to the very core of the planet Earth. Their work is complicated by conflict with a mysterious intelligence deep within the Earth and by the robot's own emergent humanity. The remaining stories comprise a variety of tales including a story about mountain climbing in the Chilean Andes in which the protagonist is haunted by a ghost, and a tale about a battle-weary veteran who returns from a high-tech future only to face his greatest and most sinister challenge right at home.