It’s like The Thing + Alien in space and part of the plot involves a guy who’s on the run for murdering some guys who got his sister addicted to drugs and forced her into prostitution. A detective from earth followed him onto the ship, but like… by the time he arrests him and goes home, 50-60 years will have passed. Everyone who has any interest in seeing the guy arrested has long since died. His warrant for arrest is just a tally in a computer database, and the detective will have given up everything he ever knew and anyone he ever loved to arrest this guy for no real purpose or gain for anyone.

The captain is chronologically 240 years old at this point and he’s seen it himself. Every trip he’s ever been on, you come home an anachronism, a living fossil, uselessly out of date. So you go back up, you go on another trip, and another, until you die in space as lonely as you would have been on earth