A remake of the 1982 Mugen Shinshi Kaiki-hen.

Note: In the afterword to Shin Kaiki-hen, it was stated that Shin Kaiki-hen is a sequel to this and a seperate story like Ouma-hen and its sequels. Due to that note, this version of Mamiya is considered to be either a brand new "Seinen tantei D" or another version of "Seinen tantei C."