I have visited historic murder scenes in London several times, prompted by a film about to be made or because I had interviewed a star who had worked on one.

It probably started more than 40 years ago, when I heard that Dickie Attenborough was to star with John Hurt in a movie called 10 Rillington Place. The film was about the famous post-war serial killer John Christie, who killed and buried several women, including his wife, in the house of that address.

Before filming began, I took myself to look at the real-life murder house, which was situated in a very seedy, dead-end road –  and that is not meant to be a pun. If a house could smell of evil, that one did.

They used the actual road for the exteriors – buy it on DVD and judge for yourself. Dickie gave a superb performance and in its day the case caused a sensation.

Not long after filming was completed the local council demolished the road. I hear the demolition crew made some extra money by selling the front door to 10 Rillington Place several times. They simply removed identical doors from other houses in the road and popped down to the local Woolworths and put the number 10 on them.

The whole area is now different, the roads altered and a bit of green land now occupies the site of that notorious house.

At the end of the 1970s, I was told they were going to shoot a film at Elstree with an all-star cast, in which Sherlock Holmes tackles Jack the Ripper, called Murder By Decree. I think it is an underrated film and you should watch it.

I recall visiting the realistic Whitechapel streets interior sets and interviewing veteran star James Mason, who was playing Dr Watson.

James told me: “I actually started my screen career in Borehamwood in the early 1930s but was sacked after a few days when the director said I had no future in movies. I have approached the character of Watson as an intelligent friend of Holmes. He is often portrayed as a bumbling joker but he was supposed to be a medical doctor and Holmes would never have shared his life with an idiot.”

To get a feeling for the real story, I went with a handful of friends on a walk around the real murder sites on the 90th anniversary of the crimes. Whitechapel was already beginning to change rapidly, but in 1978 the scene of one of the murders was still unchanged.

It was Mitre Square, which you entranced through a dark passage and the cobbled square was surrounded by Victorian warehouses. I must admit it felt eerie to stand in the footsteps of Jack the Ripper and his infamy still fascinates the world today.

I also remember interviewing Donald Pleasance years after he portrayed the infamous Dr Crippen at Elstree and he told me that at one time as a hobby, he used to go to the public gallery at the Old Bailey to listen to murder trials.

The infamous Crippen house was demolished after the war but the police allowed me to occupy his cell, albeit for a few minutes, at Bow Street Police Station, which he had occupied after his arrest. He is famous for having been caught fleeing aboard a ship to America.

The Metropolitan Police twice invited me to visit the world-famous Black Museum at Scotland Yard, although I think they now call it the Crime Museum due to complaints. It is fascinating and includes a death mask of Nazi monster Himmler, gory exhibits from famous murders of the 20th Century and one strange item that drew my attention.

It was a hand, floating in a jar of preservative fluid. I asked about it’s origin and was told that someone suspected of murder in England escaped to Germany where he murdered again. He was executed over there and Scotland Yard asked for his fingerprints so they could close their case file. The ever-efficient Germans cut off his hand and sent it so Scotland Yard so they could take their own prints.

I even got to interview the famous Albert Pierrepoint, who hanged hundreds of people as the official British hangman, including some infamous names. He even played criminals at Hendon Police College, but they are tales for another time.

Meanwhile, as Shaw Taylor used to say on Police Five, one for the older readers, “keep them peeled” and as Crimewatch says, “don’t have nightmares”. I would look under your bed tonight, just in case.