Isidore Newman was born in Leeds in 1916, the son of Russian Jewish immigrants. He grew up in Durham, where he trained as a primary school teacher before moving to Hull in 1938; his family soon followed when his father's cloth business went bankrupt. He joined the Royal Corps of Signals in August 1940 and was posted to an AA battery in Sheffield, before joining SOE in July 1941.

His background as a signalman was ideal for the job of wireless operator, for which F Section had a great need, and he began training immediately, taking on the pseudonym of 'Matthieu Elliot' to disguise his identity from other recruits. The course instructors soon noticed his less than perfect French - he'd studied the language at university, but had only spent a couple of weeks on the Continent, travelling across Belgium and northern France - and they also had some concerns over his moodiness during his commando training in Scotland, but he proved himself a determined and dedicated student.

His first assignment would be to support Francis Basin's URCHIN circuit on the Cote d'Azur. In April he left Gibraltar with fellow agent Edward Zeff, travelling by submarine to the Riviera coast: their escort was Peter Churchill, who guided them in canoes to the Pointe de l'Illette, situated just outside the old walls of Antibes and yards from the home of Basin's contact Dr Levy. After some minor problems finding a good safe house, Newman began his new secret life as 'Jacques Nemorin' and - using the codename Julien and call-sign of Dividend - began transmitting URCHIN's telegrams the following month. He got on well with Basin and everything went smoothly until Basin was arrested by French police in August; Churchill was then brought back to replace URCHIN with SPINDLE, a new circuit that would work more closely with André Girard, self-appointed head of the local CARTE organisation. SOE had great hopes for CARTE, and Churchill's job would be to get the best out of it.

Newman was not impressed by his new organiser's security and soon found it necessary to keep on the move, shifting between safe houses in and around Cannes. He was also becoming bogged down with an increasing workload. Girard - now Newman's boss as much as Churchill - refused to abbreviate his long-winded, wordy telegrams to London. Churchill preferred not to interfere. Even with the help of newly arrived wireless operators Harry Despaigne and Harry Peulevé, Newman was forced to transmit through the night to shift the backlog.

Despaigne and Peulevé quickly washed their hands of CARTE and headed for Spain, but Newman felt a responsibility to stay on. Churchill had other ideas, though. He'd taken a stray wireless operator, Adolphe Rabinovitch, under his wing, and wanted him to replace Newman. Frustrated, confused and exhausted - he'd sent nearly 200 messages since arriving in March - Newman had little choice but to comply, and was put aboard the November felucca back to Gibraltar. He submitted a critical report on Churchill's and Girard's conduct when he arrived back in London a fortnight later.

Although he must have felt drained by the last eight months, he immediately volunteered for a second mission. Buckmaster agreed to send him to a new circuit but his flight was postponed at the end of December due to bad weather, and a wireless refresher course was arranged for him instead. In fact it wasn't until July 1943 that he left for France again, this time to join the SALESMAN network in Rouen and Le Havre, arriving by Lysander at a landing ground near Tours.

SALESMAN had been running since May, but was in need of a reliable radio link with London to begin coordinating supply drops. Its organiser, Philippe Liewer, arranged for Newman to stay with Denise Desvaux, a dressmaker living on rue de Fontenelle in Rouen: operating under the new cover name of 'Pierre Jacques Nerault' and codenamed Pepe, he would pose as her nephew and business associate. After living under CARTE's lax security the previous year, Newman made use of Liewer's contacts and quickly set up three separate radio posts. He reportedly cycled 1500 kilometres a month between them, accompanied by a bodyguard, never transmitting more than twice from the same location before moving to the next.

The department of Seine-Maritime was heavily garrisoned, but SALESMAN made effective use of the arms it was now beginning to receive: in September it sank an 800-ton minesweeper, and wrecked a local power station the following month. The circuit's security was excellent but Gestapo agents soon began flowing into the area, and German radio direction-finding teams came very close to hunting down Newman, even deducing the times of his transmission schedules. He was forced to stop work altogether for six weeks, in case they got any closer.

In February 1944 Liewer returned to England, leaving SALESMAN in the hands of his lieutenant Claude Malraux. His group successfully derailed a troop train later that month but in early March the organisation quickly unravelled. Carrying the weight of the whole network was too much for Malraux: he failed to act when a couple of resisters were arrested, and on 8 March he himself was captured in Rouen. Within hours almost all of his contacts were blown. According to Liewer's later report (he returned in April and sent his assistant Violette Szabo to Rouen to find out what had happened), Newman had been expecting Malraux to arrive for dinner that evening, and became worried when he failed to show. He informed his bodyguard that he was cancelling his next transmission and would move to another safe house twenty miles away the next afternoon, but he and Madame Desvaux were too relaxed. The following day they decided to have lunch with Malraux's fiancée before leaving, crucially delaying their departure. The Gestapo arrived moments after they'd finished eating; Newman made a run for the back door, but was caught instantly and handcuffed.

The evidence gathered by Liewer and Szabo suggests that he gave away the locations of his safe houses almost immediately - the six families who had sheltered him were taken away the next day - and although Malraux had initially been beaten, neither man was tortured (after being released, Desvaux was allowed to visit them three times a week at the Palais de Justice and reported that both were in good health). In April they were moved to Compiègne camp; a week later a bus took them to Paris, first to the Gestapo prison at Place des Etats-Unis, then Fresnes prison. The captured agents who boarded it along the way included BUTLER's organiser Jean Bouguennec, and his wireless operator Marcel Rousset; Canadian agents Frank Pickersgill and John Macalister, and arms instructor George McBain (ARCHDEACON); PROSPER's Gilbert Norman, 'limping terribly' according to Rousset after being shot during a recent escape attempt; John Young (ACROBAT); and Edward Wilkinson (PRIVET).

Their destination was Rawicz prison in Silesia (now south-west Poland), which took four days to reach by train. Conditions here were bad. Rousset reported poor food, only 15 minutes daily exercise and all of them were kept in solitary confinement. In May Rousset, Pickersgill, Macalister, McBain and Garel were recalled to Paris for further interrogation, but Newman, Norman, Young and Wilkinson remained. At the beginning of September 1944 they were transferred to Mauthausen concentration camp, along with three other F Section inmates, Sidney Jones, Marcus Bloom and George Clement. During 6 and 7 September Newman and his group were shot at the camp's quarry, along with 40 other SOE agents, nearly all Dutch.