
This mystery is a prologue to tell you "Welcome back"
"Shimanami Kaido's Mystery Solving Journey - Letters and Voices Echoing in the Sea - Prequel (WEB Version)"
is a youth mystery set in Oshima, Hakata Island, and Omishima Islands on the Ehime side of the Shimanami Kaido.
First, to the site and try to solve the mystery left behind by "My Father"!
Your partner to solve the mystery is "Me", and you will be accessing it.
Start the "Me" chatbot on the right side of the "You" screen and try deciphering the mystery scattered around the site with your partner "Me" ♪
The mystery you see may not be everything...

[STORY]
My beloved father suddenly disappeared. Leave this pendant for me.
Time passed, and on the night of my 18th birthday, my mother handed me an envelope.
features several letters written in my father's letters, a watch that my father used, and...
and! ! !
March 31st, 2025 - [Local Edition] Shimanami Kaido's Mystery Solving Journey - Letters that weave your feelings and voices reverberating in the sea -
will begin!
Details will be announced around March 15th.
Or maybe "I" and "You" who solved the mystery of the web version have some clues about the local version too...! ?
- [WEB version] Shimanami Kaido's Mystery Solving Journey - Letters and Voices Echoing in the Sea -
Released from March 1st, 2025 - [Local Edition] Shimanami Kaido's Mystery Solving Journey - Letters and Voices Echoing in the Sea -
From March 30, 2025 to November 20, 2025 - Participation fee: All are free