Who is Robbie Mullen? The Walk-In character explained

Central to that triumph was Robbie Mullen, who joined the now-banned far-right extremist group National Action (NA), but became disillusioned with the organisation's fantasies of 'race war' following the murder of MP Jo Cox in 2016.

This prompted Mullen to share his insider knowledge with anti-fascism and anti-racism organisation Hope Not Hate, eventually leading to the imprisonment of Jack Renshaw.

Who is Robbie Mullen?

Robbie Mullen was born in Widnes in north west England. His father passed away when Mullen was 16, and his mother was a full-time carer for her husband before working in customer service. Mullen previously told The New Yorker about crimes taking place around him and the heroin abuse that was rife in his neighbourhood.

He struggled at school and said most of his friends later spent time in prison, and Mullen himself dropped out of education aged 14. He began taking on a number of menial jobs and it was through work that he began drifting into far-right circles. A job fitting satellite dishes saw him travel to Bradford and Blackburn, which he feared were being "taken over" by ethnic minority groups.

Working in warehouses for the likes of Amazon and Tesco also fuelled this racism. Many of his colleagues did not speak English as a first language, which he resented.

His lurch towards white nationalism was a surprise to his mother given that he had been raised in a Labour voting household that was actively against racism and anti-immigration.

Mullen's feelings of disenfranchisement from modern Britain led to him researching far-right groups on the internet, and in 2015 he attended a white nationalist march in Wigan. It was at the march where he first met a member of NA, which had not yet been outlawed.

NA's membership skewed younger than most fascist groups, which is what enticed Mullen to join them over the better known National Front. He'd meet regularly with the other members at the pub where they'd spew hatred. Their conversations, which were also prolific online, reportedly covered topics such as genocide, rape and pro-Hitler stances.

Though Mullen quickly became a popular member of National Action, his faith in the group dissipated roughly a year after joining when MP Jo Cox was murdered, in 2016. While other members of the group delighted in Cox's murder and championed the notion of "white jihad", Mullen was rattled by the group's apocalyptic vision and wanted out.

He had no desire to reach out to the police, instead contacting Matthew Collins at Hope Not Hate with information about NA. Collins himself used to be a passionate member of the far-right, but is now head of intelligence for Hope.

Mullen then remained with the organisation, filtering information back to Collins about their activities until Renshaw proclaimed his intention to murder MP Rosie Cooper and police constable Victoria Henderson.

Mullen alerted the authorities immediately and, incredibly, refused police protection, leaving him vulnerable from those still within the movement. Death threats then followed before he eventually testified against Renshaw when he was on trial for alleged National Action membership after it had been banned.

During the trial, Renshaw admitted to both threatening to kill Henderson and preparing to kill Cooper, and was convicted of engaging in conduct in preparation of a terrorist act and making a threat to kill, although the jury was unable to reach a verdict on the charge relating to membership of National Action. He was given a life sentence in 2019 with 20 years minimum to be served.

Renshaw also faced a retrial for alleged membership of National Action. The jury did not reach a majority verdict and the charges were not pursued any further.

In the aftermath, Mullen wrote a book with Collins about his experiences with the far-right and his decision to turn whistleblower, titled Nazi Terrorist: The Story of National Action. He still lives in fear that those who remain in the movement will attempt to harm him for standing against them and their beliefs.

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