Shameless star completely unrecognisable in chilling new BBC drama

Shameless actor David Threlfall couldn't look further away from his former alter-ego Frank Gallagher even if he tried, inBBC's new drama feature, Unforgivable.

The dark story plot follows a harrowing tale that centres around child grooming and sexual abuseand shines a light on how a heinous crime can ripple through an entire family, with the Mitchells at the heart of the 90-minute long feature.

David, 71, who is best known for his alcoholic, chain-smoking days as Frank on the popular working-class comedy sitcom, has ditched his iconic long dark locks to star in the role of Anna Mitchell's father.

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Anna, is a mother of two children and her brother Joe is the perpetrator - who had been behind bars serving a two year prison sentence for his despicable crimes.

Joe is now to be released from jail and undertake rehabilitation which takes further toll on Anna, who is played by award-winning actress, Anna Friel, as she attempts to deal with the aftermath and emotional strain.

David plays the angry dad of Anna, after learning she'd been to visit her brother Joe, despite his chilling crimes. His character in Unforgivable appears to be worlds away from his former head-of-the-clan character Frank on Shameless.

In the brand new production, the esteemed actor is totally unrecognisable, boasting short gray hair and a neatly trimmed matching beard.

Another distinctive observation that'll no doubt throw fans off of his Frank Gallagher scent, is that he is also presented as a well kept man, sporting a black tie and blazer with a crisp white shirt - nothing like his oversized green parka-style coat from a past on-screen life.

Previously, David's appearance and accent have also proved to be a talking point among baffled fans with the actor bearing no real-life resemblance to his character at all.

He played Frank so well, that viewers were unable to get past that he may not be anything like him off-screen.

Shameless aired on Channel 4 for eleven series and 139 episodes from 2004 until 2013 and was adapted in the US, where it ran between 2011 and 2021.

Speaking about his pursuits away from television, David previously shared with the Mirror that he is a family man at heart, sharing two children with his accomplished actor wife, Brana Bajic.

Underscoring the disparity between himself and his fictional counterpart, he told the publication 2010: "I can't imagine getting up in the morning and taking a drink. My body doesn't take more than four pints. I was doing a scene yesterday where he was drinking cough medicine. He's lost."

Unforgivable will air on BBC Two at 9pm this Thursday and will be available on BBC iPlayer from the same day.