With its large elongated smile and its ability to appear and disappear at will, the Catbus is reminiscent of the Cheshire Cat from Alice in Wonderland. Often used to transport Totoros, in the film it makes an exception to help O-Totoro, the main Totoro, who is also the biggest. O-Totoro calls the Catbus and asks it to help Satsuki find her lost sister Mei.