S2·E20 Turner's Imaginary Friend

Fred performs an experiment from a book called ""My Forbidden Experiments"". At first nothing happens, so he leaves. Later on, the machine works and an elf-looking guy comes out from another dimension. After going upstairs, he finds out that no one can see him except Turner. The next morning Fred and Casey find the kitchen ransacked. They blame Turner, who then blames Falslag. Since they can't see him, they think Turner made up an imaginary friend to take the blame. That night, Falslag tries to go back where he came from. Turner goes down to help him and makes a lot of noise. When Idella, Fred, and Casey come down, they blame Turner for turning the machine on. He then had them clap their hands to show they believed in Falslag, and he magically appeared before their eyes. They all apologized to Turner, and Fred promises to find a way to send Falslag back.