Clark attended King's College, Cambridge, before leaving at the age of 18 to join the Royal Naval Volunteer Reserve during the Second World War.

He led Hill Samuel through their takeover by TSB before Maxwell brought him on as a non-executive director at his Mirror Group of media companies.

Clark claimed to be ignorant of Maxwell's £492 million defrauding of the company and its pension scheme, and faced a non-confidence vote by the shareholders.

[1] During initial training at HMS Collingwood, near Portsmouth, Clark discovered that he was colour blind and only passed the medical examination by persuading the man sitting behind him to whisper the answers to him.

[1][4] Frustrated at not being able to fight the enemy directly, Clark volunteered for service with the Special Operations Executive (SOE), an irregular warfare unit, in June 1943, having claimed to have had experience working with small boats.

[4] He was attached to the SOE's No 1 Special Force and undertook amphibious sabotage, reconnaissance operations and running of agents into enemy-held beaches by canoe.

[5] Clark volunteered for parachute training with SOE and was subsequently allocated to Operation Clarion, the designation for British assistance provided to anti-German partisans in northern Italy.

[3] When Clark made his parachute jump he had Falla, his childhood teddy bear, inside his battledress for comfort and good luck.

[1][2][3] Clark managed to avoid summary execution at the hands of the Germans and was held in several Italian prisons where he was interrogated frequently.

[1][6] Clark intended to move to Sudan after the war but a chance meeting with his old commanding officer, Hilary Scott, in St James's led to him being offered a position as a clerk at the law firm of Slaughter & May.

[1][3] At Slaughter & May, Clark worked exclusively for the firm's merchant bank clients and was involved in the bitter takeover of Millspaugh by Hadfield.

[3] He chaired the National Film Finance Corporation from 1969 to 1976 and sat on a committee to represent Rolls-Royce's creditors during the nationalisation process.

[2] Benn bore him no ill-will for this and in 1974 asked him to join the government committee into the future of ailing car-makers Austin and British Leyland.

[7] He was knighted on 10 February 1976, receiving the honour from the Queen at Buckingham Palace, and became a director of the Bank of England on 4 June, following the death of Sir John Norman Valette Duncan.

[1][7] He was on the boards of many other companies, holding directorships at Eagle Star (1976 to 1987) Royal Dutch Shell (1982 to 1994), Vodafone (1988 to 1998), IMI (1981 to 1989) and Marley (1985 to 1989) – he later became the first non-family chairman of the latter.

[2][7] He served on the Review Body on Doctors' and Dentists' Remuneration from 1979 to 1986 and was a trustee of the Charing Cross and Westminster Medical School from 1981 to 1995.

[7] He was also chairman of the United Drapery Stores, where he was responsible for refusing a takeover bid from Heron Foods before accepting one made by Hanson plc.

[2] Clark claimed that he tried to make Maxwell follow conventional business practices and remained convinced that "until quite close to the end, he never did anything I asked him not to do".

[2] Clark claimed that there had been no evidence for the directors to act on against Maxwell, telling the shareholders at an extraordinary general meeting (EGM) that "No system of internal control, however elaborate, can stop fraudulent collusion by a group of individuals holding authority and trust.

[2] At the EGM Clark almost lost his usual polite nature when he was accused of being a Maxwell "crony" by Rupert Allason and had to rule a no-confidence vote as out of order.

[2][3] Clark brought in David Montgomery as chief executive officer and Lord Hollick as a director to rebuild the company.

[1][3] He collected teddy bears, having more than 300 in total (including Falla), and was also interested in the life of Captain Cook, retracing one of his voyages himself.