Trouble-making police detective Boyle Samejima, who is not averse to breaking rules to get the job done, is transferred from Shinjuku, Tokyo to the laid-back Ogasawara Islands. Now at the Anegashima Police Department, Samejima investigates the bizarre unsolved case of "The Cult of the Sea" (海の教団), where a religious cult who worshiped a little girl as their oracle suddenly vanished. That little girl, Chako, has recently returned with a humanoid dolphin named Orpheus, whom she calls "Papa." Orpheus joins the police department on the same day as Samejima, as his partner and superior.
Boyle is a cop who tries to play, "The Loose Cannon". Though rough around the edges, he does take his job seriously, and will put the lives of others first. He is often called by his nickname Shark.
Orpheus F. Lipper (オルフェウス・F・リッパー, Orufeusu F Rippā)
A humanoid Dolphin and Boyle's partner. Like Boyle, his is rough around the edges, but still someone who would risk his life to protect others. He has all the abilities of a dolphin enhanced to superhuman levels.
Chako (チャコ)
The oracle of the cult of the sea. She is very much like a child with an active imagination, but has the strange ability to evolve sea life into humanoid forms, but she is not aware she has this power.
Hard-Boiled Cop and Dolphin is written and illustrated by Ryuhei Tamura. The manga was serialized in Shueisha's Weekly Shōnen Jump from June 27, 2020 to June 21, 2021.[2][3][4] Shueisha collected its chapters in five tankōbon volumes, released from November 4, 2020, to October 4, 2021.[5][6]
The series is published digitally in English language by Viz Media.[7] Viz Media started releasing its volumes digitally on November 23, 2021.[8][9]