Ridley viewers were left stunned on Sunday night when they tuned in to see a Line of Duty star make an appearance in the latest instalment of the ITV drama.
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Taking to social media, many fans were delighted to see actor George Costigan feature as Ray Trevice in the episode.
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The 75-year-old played corrupt former Chief Superintendent Patrick Fairbank in the popular BBC police drama.
Fans of the show will remember that back in series three, Patrick was exposed as not only a bent copper but a high-profile sex offender during Steve and Kate's investigation into the death of social worker Oliver Stephens-Lloyd.
One viewer tweeted: "IT'S PATRICK FAIRBANK #ridley," while another added: "After Patrick Fairbank has turned up running a record shop I'm starting to think its actually Ted undercover in #ridley."
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"Fairbank and Hastings reunited again," wrote a third viewer, prompting a fourth to excitedly respond: "OH MY GOD IT IS," while another jokingly added: "That's clearly ex-Chief Superintendent Patrick Fairbank behind all that beard. You'd think #Ridley (or whatever Ted Hastings is calling himself these days) would spot that."
George Costigan appeared in episode three
A number of other viewers couldn't help but praise the instalment, with one person tweeting: "A cosy whodunnit with a great cast. Just perfect for a Sunday night!" while another added: "Really been enjoying #Ridley."
For those who have yet to catch up on the first three episodes, the crime drama stars Adrian Dunbar as retired Detective Inspector Ridley, who is tempted out of retirement by his former protégée, Acting DI Carol Farman, who enlists him as a police consultant on a compelling murder investigation.
Adrian Dunbar stars as DI Ridley
The synopsis reads: "Turning to her old mentor for support, Carol is keen to access Ridley's unique insight into crime-solving, which has served them so well in the past.
"With more intriguing cases to solve, Ridley will be enticed out of retirement into his former role, reviving his formidable and successful partnership with Carol."
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