In August 1955, the first slim green volume, 198 pages long, appeared at bookstalls, and within four more months it had become the UK's number one nonfiction bestseller.

They were noted for their encyclopedic memories, enabling them to provide detailed answers to questions from the audience about entries in The Guinness Book of Records.

In 1965, Ross and Norris were guests on the American panel game show I've Got a Secret, where they exhibited their memorisation of the Guinness Book of Records.

[8] McWhirter advocated and lobbied[7] for various restrictions on the freedom of the Irish community in Britain, such as compulsory registration with the local police and a requirement for signed photographs when renting flats or booking hotel rooms.

[9][8] In 1975, McWhirter offered a £50,000 reward (equivalent to £530,000 in 2023) for information leading to a conviction for several recent high-profile bombings in England that were publicly claimed by the Provisional Irish Republican Army (IRA).

[11] In his 1981 book, former counterterrorism operative Gordon Winter of the South African Bureau of State Security recalled a briefing with his London-based handler Alf Bouwer warning him to be wary of McWhirter, who he claimed was a British intelligence operative and member of the right-wing, anti-immigration Society for Individual Freedom, which he described as a "front" for "disseminating Establishment-type propaganda.

McWhirter was shot at close range in the head and chest with a .357 Magnum revolver outside his home in Village Road, Bush Hill Park.