Collateral: the burning questions we need answered, character by character

Why would someone murder a pizza delivery driver in a seemingly planned, professional assassination?

That's the main question at the heart of new TV crime thriller Collateral, which started on BBC Two tonight. But after episode one, there are plenty more burning ones that need answering.

Comparable to Line of Duty in terms of its many interweaving characters, plot strands, and whiff of a wider criminal conspiracy, the show has set-up an array of mysteries to unravel.

Here are the most intriguing, character by character.

Laurie Stone

Laurie appears to be complicit - but reluctantly so (Photo: BBC)

"You're a good girl."

"Yeah, I wish..."

Hayley Squires' pizza shop manager is definitely hiding something.

Why did she put Abdullah on the fatal delivery order when it wasn't his turn? Was it just to give him a 'run', as she put it, or something more sinister?Why didn't she close when her worker was murdered, or even seem that concerned about what happened to him? Because she's that desperate to meet targets? Or because she knew what was going to happen?Did someone threaten her mother if she didn't comply with their plan? The way she looked at her mum, and broke down in tears outside, suggested much. And someone is following her.Who is the mysterious new owner she answers to, supposedly based in Boca Raton, Florida?

Abdullah Asif

Abdullah's sister Fatima is living in fear (Photo: BBC)

The murder victim was a Syrian refugee, living in a garage with his two sisters. The forensic expert noted there was nothing random about this killing. It was planned.

Was Abdullah definitely the target? If so, why?He had an English driving license which, the police noted, can't have been cheap. They also got into the country quite quickly. Was he in debt to a criminal organisation?His sisters, Fatima and Mona, seemed terrified. They were living in Aleppo, and would have been killed if they stayed. Was Abdullah's background in Syria, and the war there, a factor? Did he know something that someone powerful didn't want getting out?

David Mars

David is an idealistic MP with some strange connections to the killing (Photo: BBC)

John Simm's Labour MP has a lot on his mind.

Is his lack of time for romance due to an unwavering commitment to politics? Or is something else occupying his attention?Will his apparent dissatisfaction with the system, and his own party, play a part in the revelations that unfold?He was only married to Karen a few months. What broke their relationship apart?David seems annoyed by his leader's tougher stance on immigration. Could the killing of a refugee in his constituency be politically motivated? And designed to hurt him in some way? He has a number of strange connections to the crime.

Karen Mars

Keeping secrets? Billie Piper as Karen (Photo: BBC)

David's troubled ex-wife, portrayed by Billie Piper, was the person who ordered the fatal pizza.

Was Abdullah targeted outside her home specifically?David notes she didn't seem upset. She threw the pizza in the corner as soon as it was delivered. The actions of a stressed single-mum? Or because she was part of the conspiracy, and knew she didn't need it?What did she mean by 'she doesn't come into it' when referring to her baby? The interviewing officer found this an odd turn of phrase, even if DI Glaspie didn't.Who was she phoning immediately after the police came to question her? Was it David? Or did she call someone else first?Was she inviting David over genuinely for their child's welfare? Or did she have an ulterior motive?She grew up in Beirut - so there's a Middle Eastern connection there. Does this have any bearing?

Jane Oliver

Jane is battling the church, and the immigration system (Photo: BBC)

Nicola Walker's openly-gay vicar, one of the opening episode's most enjoyable characters, is facing political issues of her own with the church. She's also romantically involved with Linh, the sole witness to the crime, who was on Ketamine at the time, gave a false name and address - and is in Britain illegally.

Will her desire to protect her partner, and David's desire to protect his reputation, result in crucial evidence being kept from the police?She apparently had an 'episode' with David. What is the true extent of their relationship?

Mikey Gowans

Poor Mikey has taken quite the beating (Photo: BBC)

Abdullah's fellow delivery driver was supposed to take the fatal order. But their places were switched at the final moment.

Was he, in fact, the real target?The former bouncer was punched while working the door. Could he have angered the wrong person?Mikey told officers he liked Abdullah, but it also seemed like he was considering saying more about the man. Does he know something that could explain why he might have been targeted?"The police are all over us". Near the end of the episode, he was being beaten to a bloody pulp by two shady characters round the back of a club. Why? What exactly is his role in all of this?

DI Kip Glaspie

The detective has a seriously troubling case to unravel (Photo: BBC)

Carey Mulligan's shrewd cop seems to (rightly) suspect the pizza shop manager of being complicit.

She also finds it odd that no one from the Home Office or MI5 has yet leaped on the case. Is she about to find herself mired in a conspiracy of some kind?Allusions have been made to her former life as an athlete, and as a teacher. Why did she leave those careers?She has yet to speak to some of the key players in the case. Will we see her grill Karen before long?

Further talking points:

The killer is initially revealed to be a young blonde woman. Then, it is confirmed she is a hired gun. And finally, we get the revelation that she is an army officer. Was this killing sanctioned by someone in the military? Or is it a case of on-the-side mercenary work?The journalist has a point. Why was Abdullah killed on his way out of Karen's flat, rather than targeting him before he went in?According to a news broadcast, a big vote on surveillance is coming up in Parliament - which could be a potential threat to civil liberties. David's party may hold the balance. This could just be thematic window-dressing. Or it could be something more.

Collateral episode one is on BBC iPlayer now. The series continues on BBC Two next Monday, at 9pm.

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