A man wakes up on an orbital O'Neill colony with head trauma and no memory of his identity. With only his personal AI assistant to guide him, he has to explore the station, piece together a web of friends, enemies, and strangers, and uncover a major crime.

I picked this up in a bargain book store sometime in the early 1990s. It's a nice solid, unpretentious thriller with a well-realised space station and a tightly plotted Blade Runner-esque detective mystery.

I found it