Number Four was the code number of a fictional unnamed operative of the secretive criminal organisation, SPECTRE, and secretary to Japanese industrialist, Mr. Osato. A supporting antagonist portrayed by Chinese actor, Michael Chow, and dubbed by British actor, Frazer Hines, he appeared in the 1967 James Bond film, You Only Live Twice.
When James Bond follows the assassin of his Japanese contact Dikko Henderson, he goes to Osato's company and finds a safe that tells him a few things, namely a large order for "lox". Though mistaken for fish, Tiger Tanaka deduces that "lox" is shorthand for "liquid oxygen", a component used in rocket fuel, and as such Osato must be supplying Blofeld with fuel. Posing as Mr. Fisher from the British company Empire Chemicals, Bond pretends to be interested in a contract with Osato Chemicals. He is warmly greeted by Number Four (Osato's secretary), who watches Bond via CCTV cameras throughout his meeting with Osato.
He is present in Blofeld's Volcano lair control room, when it is revealed that "Mr. Fisher" is actually 'dead' SPECTRE enemy James Bond. Number Four also provides the Tannoy voice over for the lair announcing the countdown for Bird One's takeoff. After the lair is attacked by Tanaka's ninja army, the control room explodes during the battle, and Spectre 4 can be seen running out of the burning control room along with several other technicians. It is presumed that he died in the massive explosion of the lair and the eruption of the volcano.