Members are typically referred to by number rather than by name. In the novels, the numbers of members were initially assigned at random and then rotated up by two digits on a once-a-month basis to prevent detection; for example, if a SPECTRE operative is titled "Number 1" in the present month, the security system will designate them "Number 3" in the next month, "Number 5" in the following month and so forth. However, in the EON films the number indicates rank within the organisation: Blofeld is always referred to as "Number 1" and Emilio Largo, in "Thunderball", is "Number 2". This particular example of numbering is perhaps deliberately borrowed from revolutionary organisations, wherein members exist in cells, and are numerically defined to prevent identification and cross-betrayal of aims. By deliberately drawing attention away from the true leader of the organisation, he is protected by masquerading as a target of lower importance, and the structure of the organisation is also obscured from intelligence services.