'One for the road'

Despite John Knight's apparent success in business, he had one burning ambition - to pull off the perfect crime.

Watching a Security Express van unload one day in his local high street, he hatched the idea of carrying out an audacious raid on the van's depot in Curtain Road, London EC1.

The raid needed careful planning, so John found a secret vantage point, from which he and other members of his hand-picked team of professional armed robbers could observe the comings and goings at the depot without being seen.

Through a mixture of observation and inside information, John worked out the daily routines of the guards, and, over the course of more than a year, identified the depot's security flaws.

He discovered that the depot was most vulnerable early in the morning, when the sole guard on duty would routinely leave the depot by the back door and walk across the depot's yard.

John laid plans to carry out his raid on Easter Monday, 1983.

All photographs Metropolitan Police