He has been present in the Japanese production since it premiered in 1983, but was temporarily cut in 1997-1998 (Sapporo run), with Tumblebrutus doubling as Macavity instead.
He is a very quiet cat who generally stays in the background. He supports Gilbert's aerial swings during "Jellicle Songs for Jellicle Cats", and as Grizabella begins her ascension to the Heaviside Layer, he removes the steps leading up the giant tire such that the tire can move to the front of the stage as it lifts off the ground.
The performer sneaks off stage during "Skimbleshanks: The Railway Cat" to change into the Macavity costume. He returns as this ensemble character after Old Deuteronomy is brought back, joining the cats in celebrating Mistoffelees.
As the double for Macavity, the performer is usually one of the tallest males, as well as being a strong dancer/tumbler.