A 34 year old, former Australian soldier called Frederick William Everest, then employed as a carter, conducted a violent campaign against the Americans in the latter stages of World War 2. Everest believed that ‘they were out to get him’. Two American officers, Lieutenant Allen C. Middleton and Chief Petty Officer John Daniel McCollum were shot dead by Everest who was eventually apprehended and sentenced to Life Imprisonment. He was initially held in Boggo Road jail in Brisbane. He then spent the rest of his life in a mental institution. 

Lieutenant Middleton was shot dead as he was about to leave a public toilet near Customs House at about 3 pm on 11 January 1945. A newspaper article in the Truth (Brisbane) on 21 January 1945 suggested an espionage angle theorising that there was a link between the murder of Lieutenant Middleton and a major fire in the Walter Reid building in Charlotte Street, Brisbane on the night of 5 November 1944. The article indicates that Lt. Middleton was a member of the US Army Signal Corps and that his work was of a highly secretive and confidential nature. Section 22, a top secret American Radar Countermeasures unit utilised the top floor of the Walter Reid building. The fire in the Walter Reid building apparently started on the top floor of the building and destroyed irreplaceable and extremely important military records.

The Truth newspaper article suggested that Military Intelligence, the Commonwealth Security Service, U.S. Intelligence, RAAF and Naval Intelligence were all interested in tracking down the possibility that sabotage was responsible for the fire and that spies were responsible for the murder of Lieutenant Middleton. The Criminal Investigation Branch CIB investigation was led by Inspector Jessen.

Chief Petty Officer McCollum was shot dead on 24 January 1945 on the verandah of his rented house at Denman Street, Alderley. Everest used a sawn off .22 calibre rifle.

Petty Officer McCollum had been living at a house called "Passchendaele" which was owned by Mrs Olive Brown's husband's father. The house had been rented out since June 1943 to US Naval officers.

Frederick Everest was given the title of the "Man in the Grey Suit". In court Everest said that he had enlisted in the Army in 1941 and was discharged in the middle of 1944. He had not served outside Queensland and only served at Fraser Island. A witness said that Everest had first served in a motor company and later in a works and park company.

Roy Stephenson remembers seeing the "Man in the Grey Suit" in the Prison Section of Ward 15 at the Royal Brisbane Hospital in 1973. He was reportedly dying of cancer at that point in time.

I did a search of the WWII Nominal Roll. There is no Frederick William Everest, but there is a Fredrick William Everest (Q191146), who was discharged on 29 May 1941 from 3 Workshop and Park Company. This is probably the "Man in the Grey Suit".