George Carlin stated in his last memoir that he liked young children coming up and talking to him in public places, recognizing him as the conductor from this series.
Brian Edward O'Connor improvised much of his dialogue as Schemer. He also came up with the idea of his single hair curl, as well as his garish costuming (which he said belonged to his father). In fact, O'Connor improvised so much during filming that he was eventually given credit for Additional Material.
In an interview with the Archive of American Television, George Carlin stated he took up the role of Mr. Conductor from Sir Ringo Starr so he could show off another side of his personality, other than the raunchy stand-up comedy for which he was known. He often stated that this made him the "anti-Pete Best".
A fourth season was considered, but George Carlin knew his schedule wouldn't allow him to continue full time as Mr. Conductor, the main character. So several made-for-television movies were made to follow the third season.
Veteran actor Lloyd Bridges made a guest appearance in the Christmas special as Mr. Nicholas, a kind elderly passenger waiting for his train on Christmas Eve.