In the middle of the summer holidays, the body of a drowned man with ligature marks on his wrists is recovered from Tammerkoski river. The investigation by Koskinen's team is further strained by the hit-and-run case of a dubious music manager and the mysterious Carl Friedrich. When a new body is found in Lake Näsijärvi, the connection between the victims is made clear.
Unfortunately the movie Koskinen is not yet available on Disney Plus.
| Production | Erna Aalto | Producer |
| Production | Ella Piesala | Executive Producer |
| Production | Ilkka Hynninen | Executive Producer |
| Production | Jussi Lipponen | Executive Producer |
| Directing | Lauri Nurkse | Director |
| Writing | Seppo Jokinen | Novel |
| Camera | Tero Molin | Director of Photography |
| Art | Tomi Lauri | Production Design |
| Editing | Jussi Autio | Editor |
| Writing | Riku Suokas | Screenplay |
| Writing | Heikki Syrjä | Screenplay |
| Costume & Make-Up | Jaana Aro | Costume Design |
| Camera | Jouko Piipponen | Camera Operator |
| Crew | Jouni Kivimäki | Stunt Coordinator |