Amazon freebie novella here, about 100 pages, pretty decent if you like classic science fiction and don't mind if it focuses more on action and adventure than introspection.
Ras Hume, a spaceship pilot now sunk to interplanetary hunting safari guide, discovers a long-lost spaceship crashed on an unexplored planet (no survivors) and has a bright idea. He visits a Mafia-type crime lord and proposes a huge scam: take an orphaned and aimless young man, illegally brain-wipe him so he believes he's the shipwrecked heir to a huge fortune, drop him on this empty planet (with some careful preparation so it looks like he's been there for a few years, since the ship crashed), and then "discover" him. Fortunes made! (Okay, DNA testing was about 20 years in the future when this was written, but still, this plan seems like a long shot. And I don't think the story ever explained how exactly getting their young man accepted as a missing heir was going to redound to Hume's and the crime lord's financial benefit. But moving along ...)
So everything goes great with this scheme, until suddenly it doesn't. Their young man isn't as completely brain-wiped as he was supposed to be, and something intelligent, malignant and deadly on the planet has plans of its own.
This was written by Andre Norton in 1961 and it's very much of its time. I was a little surprised that Norton, a woman, made all of the characters in this story men, but again: 1960s SF. I know Alice "Andre" Norton deliberately adopted a masculine-sounding name so her stories would appeal more to boys, and that's who most SF was written for back then. (She once told a reporter that there were only about five women writing SF in the fifties, and ALL of them adopted male pseudonyms--it's what you had to do to succeed in the SF market back then.) It's not a deep or particularly meaningful story, and it doesn't give you all of the answers, but it's kind of a fun retro tale.