This government regularly saves the world from megalomaniacal super villains bent on world domination. They accomplish this through a specific branch of agents that specialize in taking on this level of criminal. These agents use numbers to identify themselves and pseudonyms to keep there true identities secret. These agents have been operating since the 1960s, and have an unrestrained licence to kill in the name of defending the government.
The individual who adopts the number and pseudonym changes when their predecessor retires or is killed on mission. They are required to perform their duties while adopting the same habits expected of their position set in place by the first of their number:
They are mandated to use a specific kind of gun, the Walter PPK
When on mission in an establishment serving alcohol, they can only order a dry martini, stirred not shaken.
They must be womanizers who sleep with any woman they come across and leave behind kids that they take no responsibility for.
When meeting someone for the first time, they absolutely must introduce themselves with their last name, then their full name.
Every agent that has adopted this role has fulfilled it with the upmost satisfaction. However, after 50 years of this, problems are bound to develop. Using the same false identity and code number will likely get that person recognized, undermining the purpose of being a secret agent. Although the individual has changed, they would still tip off the person who they are hunting, leafing to their capture and death, or at the very least, force that supervillian to go further underground.
The agent needs to perform his duties while on mission, and retain the very same habits and style of his predeccessors. How can I make this happen?