Salvation of a Saint

The husband of famous patchwork quilter Ayane Mita is found dead while she is away on a trip to visit her parents at Sapporo. Traces of arsenic poison have been found in his coffee mug. Detective Kusanagi, along with junior detectives Kaoru Utsumi and Kishitani are assigned to the case. Upon initial investigation, Yoshitaka's (Ayane's husband) affair with Ayane's apprentice, Hiromi Wakayama comes to light. All suspicion falls on Hiromi as she was the last person to see Yoshitaka alive and has no alibi to suggest otherwise. Later, it is revealed that Ayane was aware of the affair, providing a potential motive. However, the question still remained: how would she succeed in poisoning her husband's coffee while she was physically so far away from him, at Sapporo?

The plot widens as Utsumi consults Kusanagi's old friend, Manabu Yukawa (also known as Detective Galileo), a physics professor with a keen eye for detail.