Cyril Arthur Watney was born in 1922, to British parents living in Calais. His father, a descendant of the Watney family of brewers, was in the lace-making business, but bankruptcy forced the family back to Nottingham in the 1930s. Cyril won a scholarship and studied electricity and magnetism at Oxford, but he never completed his degree and joined up in February 1941.

He was commissioned into the Middlesex Regiment and trained as a wireless operator before joining SOE in May 1943. His youth and naïveté worried some of the instructors, and according to one of their reports Watney had no idea of what kind of work he was training for. When he found out, he considered leaving the course, but was inspired by the dedication of one of his fellow students: Jacques Poirier, who had met Watney's uncle in France the previous year, had accompanied Harry Peulevé out of France and was desperate to return. They became close friends, and after finishing their course in Scotland Poirier introduced him to Peulevé in London, who impressed him so much that he requested to join his team.

Watney was turned down, but he would soon be working with both of them. After Peulevé began his AUTHOR circuit in the Corrèze, he was approached by 'Colonel Vény', a leader of the military wing of the French socialist party, the SFIO. A message to London was sent, suggesting that new circuits be set up to liaise with several of Vény's groups across France, and in January 1944 Watney was paired with organiser George Hiller to begin the first of these, FOOTMAN, in the south-western department of the Lot. Parachuting to Peulevé's reception committee, Watney was put in touch with Vény's lieutenants Georges Bru and Jean Verlhac, but it quickly became apparent that reports of local Resistance were largely illusory. Two weeks after their arrival Hiller and Watney successfully carried out their first action, sabotaging the Ratier factory at Figeac, before turning their focus towards the slow and time-consuming job of recruiting people willing to fight. By moving to a different radio post every fortnight, Watney was able to remain secure, though his fear of being detected could often be overtaken by boredom and isolation.

In March Peulevé was arrested while Poirier, who had also returned to France to work as his assistant, was away in the Savoie. Watney was able to warn him by transmitting a message from a farmhouse at St Céré, which was aired on the BBC's French Service - 'Message important pour Nestor [Poirier], Jean [Peulevé] tres malade, ne retournez pas'. Fortunately he heard it, and was able to avoid arrest. With the help of writer and self-styled Resistance leader André Malraux, Poirier began a new circuit, DIGGER, and began enlisting Watney's help to arrange supply drops of arms and two new SOE team members, Peter Lake and Ralph Beauclerk.

When D-Day came FOOTMAN's force of 600 fighters left their towns and villages to join the maquis. They successfully attacked railway lines and other German communications, but political wrangling between Vény and other groups often made it difficult to coordinate attacks. On 14 July the USAAF sent 320 bombers on 'Operation Cadillac', which dropped more than 800 containers of arms and supplies to aid DIGGER and FOOTMAN, but a little over a week later Hiller was seriously injured after running into a roadblock with Malraux; Watney called in medical supplies and arranged for an aircraft to pick Hiller up, then took charge of the circuit himself. In addition to maintaining inter-departmental radio contact and continuing with Hiller's difficult and delicate liaison work, he was able to plan an attack on a German column, and also received two additional F Section men, though by September German forces had evacuated the region and command of the Resistance had been placed under purely French control. Having returning to the UK Watney was transferred back to the army, and later received the Military Cross and Croix de Guerre for his services.

After the war he worked in a variety of roles, for the Canadian government, NATO and Whitbread's brewery, and later set up his own bookshop in Hertford. He regularly attended reunions in France, and is represented along with Hiller at the Resistance museum in Cahors. He died in January 2009.