The Real Ghostbusters (1986)

S6E10 Deja Boo

In a clever ruse, the malevolent Professor Dweeb disguises himself as a harmless ice cream seller to ensnare Slimer. With the aid of his latest gadget, Dweeb aims to delve into Slimer's thoughts to uncover the weaknesses of ghosts. As Slimer finds himself powerless and confined, he can only observe in despair while the wicked Professor sifts through his recollections.