Completely baffling – this was the popular verdict on the murder of the wealthy royal hairdresser Andre Mizelas, found slumped over the wheel of his car in the middle of the Mayfair traffic on Monday, November 9th, 1970.

Mizelas, 48, was a partner in the fashionable Andre Bernard hairdressing chain, part-owning 20 salons employing 400 staff.

A woman cyclist discovered his body. He had been shot twice in the head with a .25 handgun.

No one, it seems, would have obviously benefited from his death, so there were all kinds of theories. Perhaps he was shot at random by someone who flagged him down, perhaps he had rebuffed a client, who had taken revenge, or perhaps he had tried to end an affair and was shot by a woman or a jealous husband.