We examined all the theories of who Jo Davidson is related to in Line of Duty

Line of Duty is now firmly cooking with gas after a rip-roaring episode yesterday, and the massive twist that DCI Jo Davidson is related to someone shocking capped off a wild ride.

It was a cliffhanger so good it made you forget the jail-cell garroting, the ambush, and Hastings being retired.

To recap: AC-12 dusted Farida Jatri’s house for prints and found Davidson’s DNA. Not only did this help with the theory that she’d planted the burner phones to incriminate her ex, but it also unearthed a hidden connection.

DCI Davidson’s DNA matched somebody in the “nominal” database – which means she’s related to a criminal. As Hastings pulled out the documents containing the information and uttered a “mother of God”, we glimpsed a picture.

The picture itself didn’t offer any clues, as it turned out to be a shot of Davidson.

Of course, it’s going to be someone from a past series of Line of Duty, and in the absence of any firm clues, speculation is rife. We’ve examined all the theories to try and shed some light on the mystery.

John Corbett

This has been a fan-favourite theory since the start of the series, when Jo insisted she had no family – she’s clearly keen to hide the mystery connection.

Jo’s picture of a mum who looks a bit like Anne-Marie McGillis had armchair DCIs speculating about a connection to series five’s doomed UCO in the OCG, and with Corbett’s widow featuring heavily in this series perhaps there’s a reason they’re keeping the storyline alive.

Yes, it would be wild, and probably quite embarrassing for Hastings, but the connection wouldn’t necessarily explain why the OCG seem to have her doing their bidding.

While Hastings never mentioned a sister when talking about Anne-Marie, there’s every reason to believe he might be a bit coy about his time in Northern Ireland.

But the big flaw is simply that he was a police officer, and so would be on the police database, rather than the nominal database.

Tommy Hunter

If you don’t remember Tommy Hunter, he was the main baddie in series one, who went on to live under a new identity as “Alex Campbell”, before being flambéed in the ambush at the start of series two.

Honestly, it fits. There’s the Scottish connection, with Hunter being born in Glasgow, and he wasn’t a police officer so it makes sense for him to be on the nominal database.

A connection to Hunter would be embarrassing enough both for Davidson to say she has no family, and for the OCG to use as blackmail material.

She might not be the big, bad bent copper, but the threat of exposure is enough to get her to do a few very reluctant favours for the OCG.

There’s one snag in the theory. Den Of Geek pointed out that with Hunter born in 1965 and Davidson in 1979, a 14 year age gap makes the idea of him being her Dad unlikely.

In the grand scheme of things, such a tiny detail probably isn’t enough to exclude Hunter from your enquiries – and of course she doesn’t necessarily have to be his daughter. I’d be surprised if he wasn’t the mystery relative.

Matthew “Dot” “The Caddy” Cottan

This would be scenes, but it can probably be ruled out as Dot was a police officer.

That said, Craig Parkinson, who played Dot tweeted this cryptic clue:

That wouldn’t have anything to do with drumming up interest for the Line of Duty podcast he hosts, mind.

And only a short time later he poured cold water on the theory.

Ryan Pilkington

The baby-faced bent copper has been causing havoc in the MIT. If he’s not drowning a fellow officer, he’s putting a gun to Davidson’s head.

While at this point we rule nothing out and rule nothing in, if there’s a connection, then surely it’s one not even Davidson’s aware of. And if that’s the case, then there’s no obvious reason it’d tie her to the OCG and make her susceptible to blackmail.

But then again, maybe there was nothing suspicious about her getting in his car, and her baby brother was just giving her a lift home.

Andrea Wise

Wise has been a spanner in the AC-12 works for a long time, and now she’s actively thwarting their efforts to look into Davidson’s conduct.

While this could be because she’s under pressure to make the force look squeaky clean or just straight-up in league with the OCG, a left-field explanation would be because she’s trying to protect her secret daughter.

However, Arnott clearly said the relation was a “he”. Plus, she’s a copper, so wouldn’t be on the nominal database. I don’t buy it, but stranger things have happened.

Nigel Morton

Dodgy Nige with the fake limp hasn’t showed up on screens for a few series now. It’d be a good throwback, but once again I refer you to crucial evidence in this case: the person Davidson is related to is a criminal, not a police officer.

Mike Dryden

See above. Discount him from your investigation.

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