The three investigators want to go on a road trip during their vacation, but just as they are about to set off, the phone rings and an unknown caller hands the trio of detectives their latest case: the archaeologists belonging to the secret society Sphinx are carrying out illegal excavations and selling the stolen art treasures. Their next target is the supposedly cursed island of Makatao.

A famous trio of young detectives embark on an internship on a film set in Transylvania. As they arrive at Countess Codrina's castle, strange events unfold, connecting a decades-old missing boy case, a secretive brotherhood, and an enigmatic undead. Their friendship, the filming, and Peter's relationship with his father are all at stake as they delve deeper into the mysteries.

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.