A twelve year old girl named Mint wants to help people's hopes and dreams.
Set in Hinomoto, a fictional version of Japan, where for a long time railway travel served as the most important form of transport.
Layton Mystery Tanteisha: Katori no Nazotoki File (Layton Mystery Detective Agency: Kat's Mystery Solving Files) takes place during the events of 'Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy'.
The story follows the everyday lives of students and teachers at the Private Amaka Academy, a school established by the the large university town group Slive Central.