Hong Kong fell on Christmas Day 1941. There was little thought of playing a future role in the anti-Japanese struggle amongst the scared and dispirited British. By the end of January the soldiers were in military camps in Kowloon and almost all of the civilians were in Stanley Camp well away from the Island’s centres of power and military activity.
A small force of British soldiers had been left behind Japanese lines to carry out sabotage operations, but the only large resistance organisation in early 1942 was a troop of guerrillas based in the NewTerritories. Although the main stress in the agit-prop through which they sought to win the ‘hearts and minds’ of the villagers was on patriotic opposition to the Japanese, they were already dominated by communists who attempted to put into practice Mao Zedong’s teachings on guerrilla warfare, and in December 1943 they were explicitly declared to be ‘under the leadership of the communist party’. The name they’re best known by is the East River Column.
One of the Column’s activities was helping Allied POWs escape, and in January 1942 they assisted in the escape of Lindsay Ride, the head of the HKVDC Field Ambulance, from Shamshuipo Camp – Ride was taken out of the camp by a Chinese student Francis ‘Chicken’ Lee and ‘due more to a stroke of good luck than by design,’ the party arrived at the outskirts of the guerrilla stronghold of Saikung (NT). The ERC helped the escapers through to Free China and thus began a fruitful cc-operation.. Ride was originally motivated by the belief that if someone didn’t get medicine into Shamshuipo then the summer would see the inmates die in droves of epidemic diseases, but the organisation he set up, eventually called the British Army Aid Group, was a wide-ranging resistance network which played an important role in escape, evasion and espionage, functions they carried out in cooperation with the ERC. More than this, just as Ride’s original break-out from Shamshuipo was only possible because of Chinese help, the BAAG itself depended on Chinese agents at every point, as only they could move with any degree of freedom into, around and out of occupied Hong Kong.
One of these Chinese agents was Yeung Sau Tak, who worked before the war as a draughtsman at the Naval Dockyard. He kept his job during the Japanese occupation, successfully convincing the Japanese he was in favour of the New Order, but remaining in fact pro-British.
About October 1942 he was approached by Loie Fook Wing (David Loie) one of the leading Hong Kong agents of the British Army Aid Group and agreed to form part of the espionage network he was establishing. I assume Mr. Loie approached him because they were both in the Hong Kong Police Reserve, Loie an assistant Superintendent, Yeung a Lance-Sergeant. It seems from one source that Chinese members of the Police Reserve formed an underground resistance network even before the BAAG sent agents into Hong Kong in June 1942. 
Loie’s group was completed by March 1943 and from then until April Yeung Sau-tak was an active participant, stealing secret military documents from his workplace, the Planning Room of the Shipbuilding Section of 2 Engineering Section, on several occasions. He copied these documents in ‘invisible’ ink and gave them to agents to be taken to Waichow. At the end of March, acting under orders from Loie Fook Wing, he set up a radio set at his dormitory room in Lockhart Road with the intention of communicating with Waichow.
His wife Chan Wai Chi (post forthcoming) was also one of those arrested for spying. They were both tried on the morning of October 19 as part of a group of 27 prisoners. George Wright-Noothde scribes what happened during the lunchtime interval:
(After beating Douglas Waterton, the court orderly Takiyawa) turned on the married couple, Yeung Sau Tak and his distraught and sobbing wife. He subjected them first to a torrent of verbal abuse and ridicule before dragging them out in front of the others. ‘Now I shall show you how I do head chopping. All watch closely.’ Grinning broadly he drew his sword and forced the wretched Mrs Yeung to kneel on the floor. She was close to collapse, while poor Yeung must surely have felt he was about to watch his wife be decapitated. Takiyawa, however, merely swung his sword down stopping just short of the neck. ‘There – you see, very simple, very easy!’
Mrs Yeung received a long prison sentence, but Yeung Sau-tak was one of the 33 courageous men and women executed close to Stanley Beach on October 29, 1943.
 See Anne Ozorio’s The Myth of Unpreparedness: The Origins of Anti-Japanese Resistance In Pre-War Hong Kong, Journal of the Royal Asiatic Society Hong Kong Branch, 2002, e.g. pages 80-81 and George Wright-Nooth, Prisoner of the Turnip Heads, 1994, 39.
 Chan Shui-jeung, East River Column: Hong Kong Guerrillas in the Second World war and After, 2009, Kindle Edition, Location 928.
 Chan, 2009, Kindle Edition, Location 917.
 Chan, 2009, Location 1186.
 Clare Branson Lau, Looking Back With Pride and Glory, Hong Kong Auxiliary Police History Book, 1914-1997, 1997, 12.
 Ride Papers, Captured Japanese Trial Document, pages 3-4. This document was kindly sent to me Elizabeth Ride. The Ride Papers are held at the Hong Kong eritage Project. The account in Oliver Lindsay’s At The Going Down of the Sun is also based on this document.
 Wright-Nooth, 1994, 183.