By Emma Saunders
BBC News website entertainment reporter
Actor Timothy Spall has had his fair share of downtrodden roles, but his latest in Adrian Shergold's Pierrepoint has a darker twist.
Albert's (right) friendship with Tish (left) comes to a sorry end
Spall plays Britain's most prolific executioner, Albert Pierrepoint, the man who hanged over 400 people between the 1930s and 1950s.
Pierrepoint, whose father and uncle were also hangmen, lived a double life as executioner and grocery deliveryman.
It was this dual existence that attracted Spall to the part.
"He was fascinating. He's an almost stereotypical northern, jolly, working-class guy who likes a sing-song and he's also the most prolific killing machine in the history of capital punishment," he told the BBC News website.
The film, which had its premiere at the Toronto Film Festival in September, centres on this juxtaposition and the ultimate inability of Pierrepoint to separate these two facets of his personality.
Set against the backdrop of a changing society, Pierrepoint follows the notorious executioner's journey as he learns his "trade", gains a reputation as the quickest hangman in the UK and sees the tide turn as the voices against capital punishment grow stronger.
Began career in 1932 and became chief executioner in 1940
Executed around 200 Nazi war criminals including the "Beast of Belsen", Josef Kramer
Holds the record for the swiftest execution on record - on 8 May 1951 at Strangeways prison, James Inglis was led from his cell and pronounced dead seven seconds later
There was no salary paid to executioners - they were paid per job
He owned a pub with his wife Anne called Help The Poor Struggler
"He felt it was a sacred art, a craft, but the toll of what he's doing wears away at him," says Spall.
Pierrepoint took great pride in his work, which Spall says helped to motivate him.
"He was like a weights and measures man, he wouldn't have to weigh anyone, he only had to look at a condemned prisoner to know how long the rope had to be."
Pierrepoint's service to the Crown is a closely guarded secret but his anonymity is blown away when he is asked by Field Marshal Montgomery to execute Nazi war criminals following the Nuremburg trials.
The scenes here are some of the most shocking - the camera lingers as Pierrepoint hangs a stream of German prisoners, in what can only be described as a production line.
"The Belsen scenes were hard work - in the first three days, I'd hanged 12 people including two young actors who are both friends of my son," says Spall.
"The execution chamber was an exact replica of the one at Wandsworth jail, it was uncanny and macabre. The whole thing was very affecting.
"The director, writer and I all felt we were channelling into something very unsettling."
Some of the most fascinating footage is that of the treatment of the bodies after execution.
Pierrepoint is seen washing them and preparing them for burial in a very careful, reverent manner, contrasting with the emotionless act of hanging them moments earlier.
Spall says he read a book written by Pierrepoint in his later years which touches on this.
Protests against capital punishment began to grow in the 1950s
"One of the most amazing things that thrilled me and made me cry at the same time was he said he received the body of the executed man in the same way that he'd have received the body of Christ from the cross."
Pierrepoint convinces himself he is just an instrument of the state but as he begins to suffer abuse from anti-capital punishment protestors, his theory is shaken.
His relationship with his wife Anne, played by Juliet Stevenson, is pushed to the limit but the ultimate test is when Pierrepoint has to hang his pub acquaintance, Tish (Eddie Marsan).
Contrary to some critics who assumed this was a dramatic device, Spall confirms the storyline is "absolutely true".
Pierrepoint hanged many people who will be familiar to the British public - Derek Bentley, Ruth Ellis and Lord Haw Haw and John Christie to name but a few.
He resigned over a pay dispute in 1956 and went on to renounce capital punishment.
"He came to the conclusion the death penalty was not a deterrent, it was merely revenge," says Spall.
While happy with the film, Spall must be feeling somewhat relieved that his next project is more upbeat.
"I'm off to do a film in America. It's a big entertainment studio movie, it's lighthearted, a bit of a fantasy and has got a lot of potential. I've got my other hat on, the English character actor."
He won't be drawn on the name of it or the subject as nothing has been officially signed yet.
Does he have dreams of winning an Oscar one day?
"I'm in two minds - it may not be fair to compare but I wouldn't be in any distress if I got one! I'd be delighted but I try not to lose any sleep over it."
Pierrepoint is released in the UK on 7 April.