A call for help from gallery owner Mr. Prentice leads the three detectives into a new adventure: his apartment is said to be haunted. When the Carpathian dog, a valuable work of art, is also stolen, events spiral out of control because all the residents have a motive. As the suspects are eliminated one by one, the three detectives find themselves in the middle of their most exciting case yet.
Unfortunately the movie The Three Investigators in The Mystery of the Invisible Dog is not yet available on Disney Plus.
| Writing | Tim Dünschede | Writer |
| Directing | Tim Dünschede | Director |
| Writing | Anıl Kizilbuga | Writer |
| Directing | Daniel Rosness | First Assistant Director |
| Directing | Paul Baumann | Second Assistant Director |
| Directing | Julia Eiber | Second Assistant Director |
| Directing | Naira Cavero Orihuel | Crowd Assistant Director |
