Arata Tendo was born in 1960 in Ehime Prefecture, Japan. He made his literary debut under his real name, Noriyuki Kurita, winning the Yasei Jidai Literary Award for New Writers in 1986 with his first ever novel, Shiro no kazoku (The White Family). He wrote screenplays for television and film before delving into mystery and thriller novels under the pen name he uses today. He most recently won the Naoki Prize in 2008 for his novel Itamu hito (The Mourner).

Ryôji Arai was born in Yamagata, Japan, in 1956. He has an illustrative style all of his own: bold, mischievous and unpredictable. Arai studied art at Nippon University. His art is at once genuine and truly poetic, encouraging children to paint and to tell their own stories. He took the Japanese picture-book world by storm in the 1990s. Since then, he has one multiple awards, including the international Astrid Lindgren Memorial Award in 2005.

David Boyd teaches translation at Kobe City University of Foreign Studies. He won the Japan-U.S. Friendship Commission Prize for the Translation of Japanese Literature in 2018 for Slow Boat by Hideo Furukawa, in 2022 for The Hole by Hiroko Oyamada, and in 2024 for Takaoka's Travels by Tatsuhiko Shibusawa.