Of all the short stories in the collection, Quartet Game is likely to be both the longest and most enjoyable for readers. In a music school, a quartet stumbles upon a mysterious score by chance, which leads them on an investigation that ultimately reveals the true power of music - the ability to drive some individuals to commit murder. This story, with its mystery-like elements and unique style from author Yoshizumi, has earned it a reputation as a cult classic. The title of the compilation volume is derived from this particular tale. Meanwhile, "Heart Beat" and "Another Day" are the other two stories in the collection.