MI5 (Security Service)

MI5, officially known as the Security Service, is the United Kingdom's domestic counter-intelligence and security agency. Its primary role is to protect the nation from threats such as terrorism, espionage, and cyber-attacks. MI5 gathers intelligence, conducts surveillance, and works closely with other law enforcement and government agencies to ensure national security. Established in 1909, it operates under the UK's legal framework and is accountable to the government, ensuring the safety of citizens while respecting civil liberties. The agency plays a crucial part in maintaining stability and responding to evolving security challenges.