Shinda Kimura wo Jouen

A threatening letter arrives at the home of a graduate of the Keiei University Drama Club: "If you want to know the truth about who killed Kimura eight years ago, come to Gokuraku Inn in Hinazuki Onsen at 2 PM on January 9th, 2024." Four people are gathered: Niwata, Sakimoto, Hatori, and Iba. On the night Kimura died, these four were in their fourth year of the drama club, and each of them had a secret they were keeping.

(Source: Kodansha, translated)