A syringe of poison the Kray twins planned to use to intimidate a witness and three gallstones found in the drain of an acid bath murderer will be seen by the public for the first time when the Met Police's crime artefacts are put on display.
The Black Museum in room 101 of Scotland Yard, the headquarters of London's Metropolitan Police, has until now only been open to officers and invited guests, including Sherlock Holmes author Sir Arthur Conan Doyle and illusionist Harry Houdini.
But, from October, around 500 items from the collection of 20,000 macabre objects will be moved to the Museum of London.
As well as the story of the East End's Kray twins, the exhibition will also tell the tales of Dr Crippen, who murdered his wife in 1910, the Great Train Robbery of 1963, and the attempted robbery of the Millennium Dome diamond exhibition in 2000.
The possessions recovered from the train robbers hideout will be put on display, along with the death mask of Robert Marley, a criminal who was executed in 1856 for the beating of a jeweller who later died and a number of execution ropes.
Sharon Ament, director of the Museum of London, said the exhibition would be "challenging and disturbing; familiar and unsettling".
"The Crime Museum Uncovered will use select objects from this extraordinary, hidden collection to consider the changing nature of crime and advances in detection over the last 140 years.
"Through focusing on people - victims, perpetrators and police officers - we'll use real objects to explore the human stories behind some of the UK's most well-known crimes, personalising what is so often de-personalised.
"And in doing so, we'll confront how, as a society, we respond when normality is shattered, lives are torn apart and we need to rebuild."
Met Commissioner Sir Bernard Hogan-Howe said: "The artefacts held in the museum will provide visitors with an insight into the evolution of crime investigation and criminal justice.
"The public will view exhibits from some of the most complex, and indeed notorious, criminal investigations carried out by the Met, and discover how such crimes were solved."
The Crime Museum Uncovered will run from 9 October to 10 April next year.