Line of Duty episode 4 review: Who is a DNA match to Jo Davidson? Who is Jimmy Lakewell and why was he killed? Do we trust Chloe? And was this the best LOD episode ever?

Mother of God, has your heart stopped pounding? Line of Duty delivers one of the all-time great episodes, stuffed with twists, action and cliffhanger questions that are going to drive us crazy for a week.

By Alex Fletcher Published: 12 April 2021 - 2.26pm
BBC Vicky McClure and Kelly Macdonald as Kate Fleming and Jo Davidson

Hastings on the warpath. Rotter Ryan unleashed. Steve Arnott seconds away from death. Surprise character comebacks and a pair of nasty farewells. This week’s Line of Duty threw the entire kitchen sink into a hour of pulsating, pedal to the floor action.

Now we really are sucking diesel.

Arguably the best episode in the show’s history and at the very least the most explosive since the infamous ‘URGENT EXIT REQUIRED’, this was a classic hour of television that viewers will remember for years to come.

Incredibly, we’ve still got three more hours left into this series. Could the tension levels go any higher? We’re not sure our hearts could take it.

But at least there’s still plenty of time for writer Jed Mercurio to explain exactly what’s been going on and answer our burning questions…

Who has DNA matching Jo Davidson and is her secret relative?

After the shoot-outs, murders and interviews, the final kicker in this week’s episode was a DNA cliffhanger.

The extra search of Farida’s house to determine whether Jo Davidson might have planted the burner phoners has confirmed AC-12’s suspicions and picked up Davidson’s DNA.

However, that wasn’t big news for us as we already knew Davidson had framed her ex.

What did come as a shock was that during the routine examination of the DNA, it matched up with someone else on the police databases. Someone that had Ted Hastings and Steve Arnott taking a deep intake of breath.

The DNA match means Davidson is a blood relative, but who is the mysterious individual? Our three top theories…

Kate Fleming -  It might explain why Davidson has been so sensitive around her. Maybe she knows it’s Kate and she’s keeping her close to protect her.

Matthew ‘Dot’ Cottan - It would explain the deep intake of breath from Steve and Ted.  And like so much of season 6, it would tie up the story with earlier seasons.

John Corbett - It would back up the Twitter theory below that John and Jo had the same mother. And it would explain why Steph Corbett has been so heavily involved in the new series.

Who is Jimmy Lakewell and why was he killed by Lee Banks?

Patrick Baladi as Jimmy Lakewell in Line of Duty season 4

We last saw Jimmy (Patrick Baladi) in season 4, when he was part of the story involving the balaclava man (“you mean balaclava men”) and Roz Huntley.

A dodgy lawyer with connections to the OCG, he was eventually caught out by Roz and AC-12 and sent down for his shifty legal shenanigans. However, he refused to divulge any information about the OCG and took all his secrets to prison rather than using them as a bargaining chip to get his own freedom.

Jimmy had been tempted into leaking information by Gail Vella, under the promise that his identity wouldn’t be revealed and AC-12 found the podcast with his interview. It was Jimmy we heard on Gail’s recordings uttering the line: “There’s some people you can’t challenge”.

Lakewell knew who was in control at the top of the OCG and also knew the reasoning behind some of their shady and despicable practices – in the little snippets we heard, he even implied there was a racist element to the operation.

However, after surviving the shootout he refused to talk to AC-12, insisting that he would never be safe from the OCG if he leaked secrets.

Little did he know, the OCG were already waiting for him when he returned from the interview and another prisoner strangled him in his cell.

Who was that prisoner? Why it was Lee Banks, who we first met in season 5. He was in John Corbett’s gang and a scummy mate of Ryan Pilkington.

Alastair Natkiel as Lee Banks in season 5 of Line of Duty

It was Banks who killed poor old PC Maneet (RIP, our heart still breaks) and who Hastings met in prison - possibly to leak Corbett's idenity as a police officer, but that still remains unconfirmed.

Banks had strong connections with the balaclava men, so it was perhaps darkly appropriate that it should be one of the masked fellas who should finally take out Jimmy.

“That’s right isn’t DI Arnott? I didn’t talk” What did Jimmy Lakewell tell Steve Arnott?

In a jam-packed episode, it was easy to forget this moment, which looks likely to be crucial to the ending of the season.

Lakewell heavily implied in his interview that he had already leaked information to Arnott, possibly in the van shortly before the shoot-out, about what he knew and who he knew was involved in the OCG.

Has Steve told anyone about what Lakewell revealed? Why is he keeping it secret? And if it was to protect Lakewell, surely he can now follow up on whatever intel and tip-off that the lawyer gave him.

When are we going to finally see CC Philip Osbourne back?

CC Philip Osbourne (Owen Teale) PCC Rohan Sindwhani (Ace Bhatti) DCC Andrea Wise (Elizabeth Rider)

CC Osbourne (Owen Teale) has become the big unseen bad in season 6. Promoted to head of the force since his cover-up and bad behaviour in season 1, he is a prime candidate to be the ‘Fourth Man’ and the final ‘H’.

Hastings has been squaring off with Andrea Wise and Rohan Sindwhani every week and is now facing not only losing his job, but the entire shut-down of AC-12 for meddling in the Vella case.

But it feels like Sindwhani and Wise are just the messengers and that Osbourne is the real top dog, who wants Hastings and his team slapped down.

Sindwhani even looked slightly regretful about the whole situation for the first time as he watched Ted leaving the building this week.

Surely it can’t be long before Osbourne reappears. We’d love him to face a showdown interrogation with Ted. It would be the most intense interview scene yet.

Did Steve Arnott’s drug-taking cost Josie her life?

There was a brief moment after Josie opened the van door, where Steve’s vision went blurry. Perfectly understandable considering the slightly tense events happening around them.

But after ignoring lots of emails about drugs testing, could that split-second indecision and an inquiry into the attack end up costing Arnott his job?

He might be able to talk his way around taking too much medication for his back, but if those drugs impeded his decision-making in a crucial moment it would probably cost him his job. Or at the very least push him into a pencil-pushing back office role.

Did Chloe set-up Jonesy? Is she working for the OCG?


During the shoot-out sequence, there was a strange moment that Jed Mercurio can’t have put in by accident.

Chloe (Shalom Brune-Franklin) attempted to climb up and open the tipped over van door to rescue Steve and Jimmy. However, she couldn’t get a grip and sent her teammate Jonesy up instead.

Jonesy managed to climb up, opened the door, but was gunned down by a man in a window.

We’re trained after six seasons of Line of Duty to trust nobody and the decision to show Chloe failing to get up on the van was a deliberate decision to get our ‘bent copper radar’ swinging into action.

Maybe Chloe is the leak in AC-12. Maybe she knew about the attack. Maybe she helped set up the attack. Maybe she knew they would be firing at Steve and Jimmy from the window as that was part of the plan. And maybe she wasn’t willing to take the risk of being the one to open the van door when shots were firing down.

It could all be a 'Jed' herring, but we've got our eye on you DC Bishop.

Who will take down Ryan Pilkington?


Rotter Ryan spent the entirety of this episode lurking. Every doorway and window that Davidson passed, Ryan was stood, staring, cold as ice.

A truly menacing villain, Ryan made it clear to Davidson that his purpose in the team is primarily to watch over her for the OCG.

When she attempted to bump him off the team, he met her outside her flat with a gun to the back of the head – the exact method used to kill Gail Vella *hint hint*- and she was quickly forced to backtrack.

The little toerag currently has the upper hand over Davidson, but it feels like he must get his comeuppance before the end of the series. Who will get the glory of taking him down? Surely it has to be Steve as revenge for the finger chopping attempts in season 1.

Will Buckells be a coward or a hero?

Embarrassed by Hastings and Arnott in his interview, Buckells was exposed as incompetent, sleazy and if not totally bent, willing to look the other way when wrong doing is going on.

He also proved himself a total coward in the closing scenes as he let Jimmy become the latest victim of the OCG as he stood shaking in fear over his cup of tea.

This confirmed that Buckells is not mastermind ‘H’ figure and that his bungling of cases was no act. But it also proves that he knows more about what’s going on than he has previously let on.

Jimmy’s death was a warning and we suspect Buckells will be a coward and keep silent for the rest of the series. However, there is still a chance for him to be a hero and risk his life to help AC-12 and end the stranglehold of the OCG.

Catch up on Line of Duty season 1-5 and the latest episodes in season 6 on BBC iPlayer.

Watch new episodes every Sunday at 9pm on BBC One.

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