Sometimes the thing you're searching for finds you, especially in mid-century fiction. There were several covers produced for Day Keene's thriller Hunt the Killer, but the three used by Phantom Books were basically identical, and you see them above. The first came in 1951, the second in 1952, and the Phantom Classics edition in 1958. You see how the art was leached of its vividness with each subsequent release. It changes form too. The gaffing hook disappeared on the last cover. Did that happen because it was too violent, or too phallic, or both? We've yet to find a satisfactory explanation for why art changed this way for a company publishing the same book multiple times. Clearly they couldn't have lost rights to the original art, or else how could they have legally copied it? But if they had the rights, why use these progressively simpler versions? In this case we suspect Phantom wanted the cover to change with each edition to give it the sense of being a new product, but that's just a guess. The truth remains a mystery for now. In any case, interesting covers for Mr. Keene.