Haruo Yuki is a Japanese mystery novelist. He won the 60th Mephisto Prize in 2019 for "Koshu Shokai no Kokeinin," which was published under the revised title "Koshu Shokai" as his debut novel. Known for meticulously constructed plots and ingenious fair-play mysteries, he quickly established himself as one of the leading new voices in Japanese crime fiction. His breakthrough novel, "Ark" ("Hakobune"), topped the domestic category of the *Shukan Bunshun* Mystery Best 10 and won the MRC Award 2022, followed by acclaimed works including "The Ten Commandments" ("Jukkai") and "Salome no Dantodai." His best-known work, "Ark," is a locked-room mystery that combines an ingenious puzzle with intense psychological suspense in an extreme survival setting.