Why does Timothy Evans’ accent keep changing from cockney to Welsh in Rillington Place?

First things first: the accent change was on purpose. The real-life Timothy Evans, portrayed in the drama by Nico Mirallegro, hopped between the two accents, constantly shifting and adapting his identity.

We asked the Rillington Place writers Ed Whitmore and Tracey Malon about the accent quirk, and here’s what they had to say: “Tim moved to London from Wales around the age of eleven, his half-sister told us he was very keen to fit in and soon adopted a London 'barrow-boy' accent, but that he could slip back into his childhood accent when around members of his Welsh family. Nico wanted to reflect Tim's malleability and that desire to fit in by using different accents according to who he was talking to.”

Tim Evans was a man used to telling tall tales –a trait illustrated in the show when his character tells a small fib about his uncle being a doctor, and also by more serious lies about his own state of employment. He was, in essence, a sort of chameleon.

Speaking about the role, Mirallegro said: “Tim was a very complex man. He moved about when he was growing up and never quite settled properly. He loved to tell stories, storifying as he called it, to make people laugh, to make people warm to him... He adopted this persona of a chap around town, a bit of a wideboy in London, but reverted to normality when he was back home.”

Evans' apparent confession is the basis of much debate but perhaps the shift in his accent goes some way to explaining why he owned up to a crime he didn't commit. His identity was constantly changing and it's possible he ended up tangled in his own web of lies and momentarily forgot which version of himself he really was.

His confusion and consequent confession could also have come from the fact that he was poorly educated – he missed vital years of school due to contracting tuberculosis in his foot. In fact, he could barely read and write, which also explains why in tonight’s episode he asks Christie to read out the house rules.

It was that combination of manipulation, poor education, poverty, shifting identity – and his choice of murderous neighbour – that eventually led to a tragic end for Timothy Evans.

The final instalment of Rillington Place airs on BBC1 on Tuesday at 9pm