13 huge questions and theories we have after Line of Duty season 6 episode 1

We've been through the episode very carefully (and very thoroughly), and here are the things we need to talk about after season six episode one:

1. Why did DCI Joanne Davidson divert the convoy?

That's the big question – so let's explore this thoroughly, because it's going to be vital to Line of Duty season six.

DCI Joanne Davidson (Kelly Macdonald) is SIO (Senior Investigating Officer) of Operation Lighthouse, which is tasked with solving the murder of journalist Gail Vella. And after information came in from a CHIS (covert human intelligence source) with an address of a man called "Ross Turner" who'd been boasting of being involved in the murder, she definitely seemed eager to go and arrest him right away.

In fact, it was only the intervention of her boss Superintendent Buckells (Nigel Boyle) that forced the whole thing to wait till morning. He okay'ed an in-situ surveillance team, but he wanted executive sign-off before giving the operation the green light. If he hadn't held things up, would things still have panned out the way they did?

However, Buckells did hold things up until the morning. And when Davidson's murder investigation team finally set off in the morning with vans full of AFOs (Armed Firearms Officers) to arrest "Ross Turner", something strange happened.

While being driven speedily through town, DCI Davidson spotted a white van parked on a side-road. This in itself is highly suspicious, because it seems odd she'd manage to see anything at all, given the speeds and angles involved. As Superintendent Ted Hastings later put it while watching CCTV footage: "That convoy is going like the clappers, you'd do well to spot a pipe band in there."

Having seen the van, Davidson immediately diverted the convoy, much to her own team's bafflement and frustration. "Did anyone see that?" she said, ordering: "Take us round the back. Take us round!" She announced that she was re-routing to possible armed robbery, refusing DI Kate Fleming's suggestion to call it in for another team to deal with: "You know a getaway vehicle when you see one, Kate. Bookie's right there. Can't rule out an immediate risk to the public."

Frankly, the whole thing had echoes of season five, when Sergeant Jane Cafferty (Sian Reese-Williams) diverted her convoy to 'help' a screaming woman whose baby was apparently trapped in a flame-engulfed car. Cafferty turned out be bent, and involved in the set-up.

Anyway. Davidson was either very astute, or she had foreknowledge that the robbery was going on – because she turned out to be absolutely correct. The armed, balaclava'd robbers came running out of the bookie's and the AFOs took them down.

It must be noted (as AC-12 later discovered) that these armed robbers had incredibly short criminal records before deciding to rob the bookie's, and certainly were not hardened criminals. DC Chloe Bishop (Shalom Brune-Franklin) quipped: "Between them, these guys have never robbed anything bigger than their local Gregg's." And as DS Steve Arnott (Martin Compston) responded: "They just happened to be on the exact route and time of an op to bring in a suspect in an unsolved murder."

Unfortunately, one of the robbers was shot after failing to drop his weapon in time, which meant that all the AFOs had to stay on the scene for "forensic recovery". (Could she have known this was going to happen? Or was her swearing genuine?)

The shooting, of course, meant Davidson had to urgently request a new team of AFOs to continue her operation to arrest the Gail Vella suspect. And so the delays got longer and longer. It also meant she had to leave her deputy DI Kate Fleming (Vicky McClure) behind, to take charge. (And perhaps she didn't want to take a former member of AC-12 to the Vella arrest op? We can but speculate).

2. Did the surveillance gap allow Carl Banks to escape?

That delay had serious implications, and Davidson's subordinates Lomax (Perry Fitzpatrick) and Farida (Anneika Rose) both felt they had lost way too much time en route to the arrest.

But the delay was made much more serious by a fact we discovered later in the episode: there was a gap in surveillance of approximately three and a half hours, during which time the real Ross Turner (that is, the man going by that name) could have slipped out of the flat at 4F Beechwood House.

Davidson did not appear to have known about the surveillance gap, which was the fault of her boss Buckells (of which, more later). None of the surveillance guys thought to mention it to her when she and the team turned up to carry out the arrest, and it was left for Kate to find out later.

"I've taken reports from the surveillance teams in situ at Beechwood House, where Terry Boyle was arrested," Kate told Davidson. "When we were diverted to the armed robbery there was some confusion over the surveillance authority.... the team was only in place under directed authority, and it got queried as requiring intrusive authority because they were using extreme high-powered lenses to view inside the property. Which means they had to pull out until it was sorted. Looks like the Super [i.e. Buckells] messed up the paperwork."

By the end of the episode, it looks like that delay – combined with the surveillance gap – allowed "Ross Turner" to slip out of the flat at Beechwood House, framing Terry Boyle for the murder of Gail Vella and leaving him behind to be arrested in his place and take the fall. Terry is a vulnerable adult with Down's Syndrome, and we've previously seen him be exploited and pushed around by members of the OCG (organised crime group).

But aside from Terry's prints, the flat was covered in fingerprints belonging to another man: Carl Banks. He is presumably the person going by the alias "Ross Turner", and he looks like a much more likely suspect than Terry. (He also might be related to Lee Banks, who we last saw in prison in season five.)

As Steve put it to Hastings, "Carl Banks has an extensive history of violence, including firearms offences, and a long association with organised crime... it would appear that DCI Davidson deliberately delayed the operation to arrest the suspect, and it's possible this was instrumental in enabling Banks – the real killer – to flee."

However, there are still plenty of things to mull over. For example: did Davidson know – or not know – about the surveillance gap? If she knew, was she colluding with Buckells, or did she realise in advance that he'd messed up the paperwork? If the surveillance hadn't been messed up, would Banks still have escaped?

3. Is Buckells bent or just incompetent?

Thinking about all of this, you have to question whether Buckells messed up the paperwork deliberately, for nefarious reasons. But he could also just be incompetent and bad at his job. When Jo called him in during the evening and asked him to sign off the directed surveillance authority, so she could get a team on watch, he was mainly focused on getting a coffee.

And why did he stall on approving the operation that night? Was it because of his distrust of the CHIS as a source of information? (The CHIS was maybe a sex worker, and we know from previous seasons that he can be very dismissive about sex workers). Was it an arse-covering decision, as he wanted to await "executive sign-off" and avoid responsibility? Was this the influence of his own boss, the Chief Constable?

Or is he bent, and did he use the delay to alert Carl Banks (and the OCG)? After all, someone had enough warning about the arrest to do a very thorough cleaning job at Terry's flat.

4. Is Kate going undercover again?

Aw, poor Kate! She's tried to put AC-12 behind her and move on to a new job, but she just can't seem to get away. And now that her old boss is looking into her new boss, she's faced with a difficult conundrum.

When Steve dropped in to give her the awkward news that AC-12 might be looking into DCI Joanne Davidson and the Vella response, she caught on quickly: "Oh s**t. Great, so when Buckells and Davidson find out, they're going to think –" and Steve finished: "Either you're our CHIS or you're embedded as a UCO. That's why I'm giving you a heads-up, Kate."

Steve offered her a choice: "We can keep it on the DL only if we've got a CHIS inside MIT."

"Great, so either I'm accused of being a traitor or I become one to avoid being accused," Kate said, and after a long pause: "I'm going to have to think about it."

However, she did then give Steve the information about Carl Banks – which was the final piece he needed to get approval for the investigation. So has she already made a decision? At the end of the episode, when she went to comfort Davidson in the corridor, and Davidson took her hand – was she already thinking like an AC-12 informant, or was she being genuine? And if she goes undercover again, what will she do about Davidson's potential romantic interest in her?

5. Is Farida trying to get back at Davidson – and Kate?

We first met Sergeant Farida Jatri (Anneika Rose) when she was a PC working for DCI Roz Huntley (Thandie Newton) at Polk Avenue. Since then she's joined the murder investigation team on the Hill (Hillside Lane), and she is the one who came to AC-12 with concerns concerning professional conduct of DCI Joanne Davidson.

But later in the episode, we discovered that Jo and Farida have actually been in a relationship, and are going through an ugly breakup – initiated by Jo, apparently because of Farida's unfounded jealousy and paranoia about other women. Farida has slashed Davidson's leather jacket in anger, but still begs her not to leave with the words: "I love you Jo, please don't go. Please don't go!"

This puts the whole thing in a new light.

Farida raised concerns with AC-12 about the diversion during the Vella operation. But why did she approach AC-12 specifically? After finding out about Farida's paranoia that Davidson is having an affair with Kate(!), you do have to wonder if she's trying to force a situation where Kate comes under suspicion for being undercover (as mentioned above) – thereby driving a wedge between her and Davidson, and ruining their friendly relationship (and imagined sexual relationship).

That said, Farida did seem genuinely distraught when she called Steve back, after the death of the CHIS (an important witness). "This is too dangerous," she said, tearfully. "You have no idea what she's capable of. None at all. Don't call me again."

So is there more to this than jealousy and revenge? What is Farida talking about here? What happened in her and Davidson's relationship beyond what we've seen in episode one?

6. Does Steve still want to leave AC-12?

At the start of the first episode, we found Steve bored and frustrated at AC-12. He was snappy, he was doing busywork, and the whole team was suffering the effects of Hastings being investigated 18 months ago (an unhappy event which left the Gaffer with a final written warning).

As ACC Andrea Wise told Hastings after freezing him out of an important meeting: "You lead an anti-corruption unit. There's plenty think you're lucky not to have been removed. Best keep your head down, Ted."

Kate left AC-12, which Hastings appears to still resent (even though Steve insists "he knows it was nothing personal"). But Steve has stayed – until now. During a coffee catch-up with a detective from another team, he told her: "I've reached the end of the line in Anti-Corruption". It's clear he's on the job hunt.

However, with a new case to get his teeth into, will he tempted to stay a little longer?

7. Why was Gail Vella killed?

We still don't actually know much about the Gail Vella case, and why she was murdered. But here is what we have learned so far: the reporter, played by Andi Osho, was murdered on 10th September 2019.

She drove home late in a Dark Grey Peugeot 108, parked outside her house in Kingsgate, and was shot dead as she got out of the vehicle. The muzzle of the firearm was pressed against back of skull (this is the "hard contact technique" - to minimise the spread of powder and blood), so the killer knew what they were doing.

A month later, Davidson was posted to the Hill, taking over from the original SIO.

The police have two working theories: a crazed stalker, or a contract killing. These are reflected in newspaper headlines from the time: "Murder Inquiry Probes 'Stalker' Theory" and "Police Seek 'Hitman'".

Given this is Line of Duty, the latter seems more likely. Was she investigating a story that someone didn't want to come out? Police corruption? Organised criminals? Surely we will soon find out more.

8. Is Steve addicted to painkillers?

From the montage of Steve buying boxes of painkillers from different pharmacies to maximise how many he can buy, and paying in cash, and then adding them to his stockpile at home, and then taking at least three times the recommended dose in one go – we'd say yes.

Steve is clearly struggling with the lingering effects of some serious injuries he's sustained on the job, most notably the time he was thrown three floors from the top of a staircase.

9. Is Terry being set up?

Probably.

Terry Boyle was arrested in the police operation to bring in Ross Turner, and the raid on Flat 4F Beechwood House. Davidson questioned him twice, and initially she seemed inclined to consider him as a plausible suspect – focussing in on the 'crazed stalker' theory.

But while Terry initially admitted to being Ross Turner when the name was put to him, he later retracted that and gave his real name, and his real address: Flat B, Dorton Villas, in the Kingsgate Area (opposite the now-defunct criminal HQ at Kingsgate Printing Services).

Both addresses, when searched, had clearly been deep-cleaned. But that Beechwood House, there were marks on the chair and door that indicated someone had tried to barricade themselves from the inside (and Kate thought the damage was quite recent).

And in Terry's flat at Dorton Villas, just like in Beechwood House, a collection of articles about Gail Vella had been pinned to the wall. Later they were found to have Terry's semen on them. Traces of cocaine and heroin were also found, as well as gunshot residue found on an item of clothing.

Terry didn't give much away in his police interviews, other than acknowledging that he recognised Gail Vella and saying that she was a "nice lady". But it seems pretty clear that he's been set up – perhaps by Carl Banks, or by the wider organised crime group, which has been using him for years.

By the end of the episode, it also seemed fishy to Davidson, who released Terry without charge. "Don't look so surprised Kate," she said. "I wasn't born yesterday. The gunshot particles aren't enough without spatter of Gail Vella's blood or tissues. And the CHIS, Carl Banks, Terry Boyle's flat, something doesn't add up... no way am I going after someone like Terry Boyle because he's the easy way out."

As an aside, I'm now worried for Terry's safety. He's been sent to "approved premises" as his flat is still a crime scene, but could he still be bumped off by whoever tried – and failed – to frame him? "You'll be safe there, Terry" his lawyer said. I have doubts.

10. Where has Terry's freezer been moved to – and what's in it now?

Well, someone has clearly moved the freezer. As the police correctly noted, a large kitchen appliance has recently been removed from Terry's flat in Kingsgate. How recently...? During the events of season five, or more recently than that?

As fans will recall, that same freezer once contained the chopped-up frozen body parts of Jackie Laverty (Gina McKee), who was murdered in season one. That's where she remained until approximately 18 months ago, towards the end of season five, when her thawed remains were disposed of at McDade & Company Breakers Yard along with the body of John Corbett (Stephen Graham).

If the freezer has only just been removed, this fact points pretty heavily to the OCG's involvement in framing Terry. It also suggests they may have had a decent amount of forewarning to clear out his flat.

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11. Who killed the CHIS?

The CHIS was an important witness, because he is the one who said "Ross Turner" lived at that flat in Beechwood House. Was he referring to Terry, or to Carl Banks? It's impossible for him to tell us now, because after passing on the information to his handler DS Marks, he went to ground. And shortly afterwards, he was found dead, having fallen from a height in very suspicious circumstances. There were no witnesses, but neighbours heard a scream.

Before his (probable) murder, Davidson was trying desperately to track him down, pump him for info, and "convey him to a place of safety". The handler couldn't ethically pass on his information, so that never happened.

But we did witness a suspicious conversation between Davidson and Buckells, with Davidson telling her boss: "If this is going to go the way we want, we've got to find out who he [the CHIS] is" and "F**k the handler, f**k the CHIS."

If this is going to go the way we want – as in, framing Terry? Or finding the truth?

12. Is that Davidson's mum in the photo?

"How come I've never met your family?" Farida demanded, while Davidson gathered the last of her things from the walk-in wardrobe. "I don't have one," Jo said. Farida did not believe her.

Then, on returning to her flat, Davidson poured herself a glass of wine. She drank some wine, then glared at a framed photograph of a younger woman (herself?) and an older woman (her mother?) on her sideboard. Then she downed the rest of the wine, and threw the glass towards the photograph, smashing it against the sideboard. (Side note: I found this whole scene unintentionally funny. Has anyone ever done this in real life?)

So, some questions. Why does she hate this person in the photograph? If that's her mum, and she hates her, why have a picture out? And if it is her mum, and it's in pride of place on the sideboard, does that mean Farida has never seen the picture or been to Davidson's flat? (Or were they properly living together, and is this a new flat for Davidson and her newly single life?)

13. Why so many locks?

That's a lot of locks on Davidson's front door. A lot. Is it meant to tell us something about her personality, or is she specifically scared of someone in particular getting in? Intriiiiiguing.

Line of Duty continues on Sundays at 9pm on BBC One. Read our latest Line of Duty episode 2 recap here. Want more Line of Duty content? Why not read our Line of Duty recap to refresh your memory on all that has taken place before season 6. Take a look at the rest of our Drama coverage, or check out what else is on with our TV guide.