As Ace and Zina were working on their new ""disappearing panter"" trick, Lt. Vega comes to the Magic Express to capture Zina. Vega is accusing Zina of being Electro City's only loose black panther and attacking a scientist named Professor Sticks the night before. Ace recalls waking up during the night to see Zina return to his room but not knowing where she went. He goes with Vega to the crime scene and is surprised at Zina'a behavior as she suddenly take off. Not knowing why, Vega takes Zina to the police headquarters for tests while Ace and Cosmo go visit a circus which seems to have a wild cat of its own. There they meet their old friend, Yokiko the animal trainer who tells them that her pet black panter, Kim Cougar being kidnapped a few weeks earlier. Things get more complicated when Zina escapes the police headquarters when she was about to be put to sleep. Fortunately though, with Cosmo's traking device, Ace, Cosmo, and Yokiko not only catch up with Zina but also found Kim Cougar a