If there's one thing Line of Duty fans deserve huge credit for, it's their level of detective work - even Superintendent Ted Hastings would be proud!
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After the BBC police corruption drama aired its explosive fifth episode on Sunday, many eagle-eyed fans took to social media to share their amazement of a huge clue regarding DCI Jo Davidson's mystery relative. Warning – major spoilers for episode ahead.
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During the episode, viewers were informed that Jo was in fact a blood relative of Tommy Hunter. But fans on social media took it one step further and paused their screens to zoom in on an interesting post-it note that was shown on the TV.
Sharing an image of the screen, one user wrote: "Did anyone else clock this post-it note? Niece AND daughter?" The post-it in question was shown to read: "Jo Davidson DNA has been identified at Farida Jatri's house. A match has been made to TOMMY HUNTER stating she is both his niece and daughter."
This aligns with episode four's ending in which DS Steve Arnott (Martin Compston) informing the Gaffer about Jo's DNA match, mentioning the word "homozygosity", which describes a genetic condition where an individual has the same DNA sequence for a particular gene from both sets of biological parents.
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One fan noticed the post-it note on the wall of AC-12
One person replied underneath the user's post: "That must have been the line about six minutes in about homozygosity…", while another said: "Holy.... wow."
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A third was theorising what this could mean for Jo's involvement with the OCG: "It's very unclear, but if Tommy abused her mother/sister it opens the possibility that he abused her, to coerce her into the OCG. Who else is blood related to this family/network to maintain the OCG after his death?"
Elsewhere in the episode, fans were left reeling after the biggest cliffhanger of the series yet – the face-off between DI Kate Fleming (Vicky McClure) and PC Ryan Pilkington (Gregory Piper) – and wondering whether it means Kate's fate has been sealed. We're already counting down the hours until Sunday!
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