The Adventure of Sherlock Holmes' Smarter Brother Sacker, shares a similar name with that originally applied to John Watson, Ormond Sacker. The film's title and premise are a joke referring to the character of Mycroft Holmes, Sherlock Holmes' "older" brother, who was by both of their estimates a good deal smarter than Sherlock. He was, however, too lazy to become a detective, and did indispensable work for the British government. Mycroft was described by Sherlock in conversation with Watson: Mycroft is mentioned briefly in the beginning of the film, which presupposes that Holmes was one of three brothers. Sigerson's name refers to an alias used by Sherlock
Special Detective Unit Special Detective Unit The Special Detective Unit (SDU) () is the main domestic security agency of the "Garda Síochána", the national police force of the Republic of Ireland, under the aegis of the Crime & Security Branch (CSB). It is the primary counter-terrorism and counter-espionage investigative unit within the state. The Special Detective Unit superseded the Special Branch (which they are still commonly referred to as), which itself replaced the older Criminal Investigation Department (CID), which was founded in 1921. They work in conjunction with the Defence Forces Directorate of Military Intelligence (G2) – the Republic of Ireland's national intelligence