In the sixth episode of the BBC drama, Macdonald’s copper repeatedly answered “no comment” while being interrogated by anti-corruption unit AC-12.
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Appearing on BBC Breakfast ahead of the finale, she refused to give away any clues on what’s set to happen next.
Presenter Dan Walker quizzed Macdonald on whether she survives, if Marcus Thurwell (James Nesbitt) is really dead, and who the fourth man is, to which the actor consistently replied: “No comment.”
At the end of the interview, she burst out laughing, and Walker said: “I’m giving up, this is pointless.”
Despite Davidson’s secretiveness in the interrogation suite, many viewers were convinced they had figured out the identity of “H” after episode five.
It’s been the question on the lips of Line of Duty fans for years: who is the bent copper known as “H”?
The last few seasons of the hit BBC One police drama have focused on the hunt for “H”, the name given to a corrupt officer working within the upper echelons of the police.
While series five revealed that “H” was in fact not one person but several, the search remains ongoing for the last “H”, also referred to as “the fourth man”.
The Line of Duty finale airs on Sunday 2 May at 9pm on BBC One.
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