Line of Duty viewers are convinced that DS Chris Lomax is working for the Organised Crime Group, ahead of Sunday's season finale.
Obsessed fans have identified a key line from episode five, that they say proves DS Lomax is corrupt.
DS Lomax name dropped a particular pub during the episode and viewers reckon it points to him being involved with the OCG.
In one scene, he chatted to a crime scene investigator, clad from head to toe in a white crime scene suit - reports Mirror Online.
Vicky McClure's Kate Fleming and Martin Compston's Steve Arnott walk towards them as Lomax can be heard announcing to his colleague that they could "be in the Red Lion bar by 8pm."
And while it was a passing comment, some fans reckon his mention of the pub is a major piece of foreshadowing and a tip off that he's a bent copper.
A Reddit user predicted: "During the telephone call Chris Lomax was on before Steve and Kate approached him at the industrial unit, Chris finished the called by saying 'meet you at the red lion at 8pm.'
"Isn't this the same pub Carl Banks boasted about the murder of Gail Vella before he was killed? Might be a OCG meeting ground."
"Oooh I didn't catch that," one replied, and referencing the order Fleming and Arnott gave Lomax shortly after, added: "He seemed reluctant to get the floors dug up too."
Meanwhile, another wrote: "Lomax said 'Meet you at the Red Lion'.....is that the same pub someone was boasting about killing Gail Vella at? An OCG haunt? #LineOfDuty."
A third said: "Also Chris Lomax is a bad 'un. Drinking in the Red Lion where he found that dodgy Devereux to falsely ID Terry.
"Also also, Ryan's mum was the one who dropped the charges against Devereux. Also also also, season 7 will be these 3 legends leading the new AC team."
*Line of Duty concludes at 9pm on BBC1 on Sunday
