Showtrial season 2 follows the story of a high-profile climate activist named Marcus Calderwood, who names a serving police officer as his killer just moments before he dies. Soon a quest for the truth gets underway as the trial of the decade begins, but not everyone is being entirely honest about what really happened the night of Marcus's hit and run.
The first episode opens with a reporter called Felix making a news report live from a SCG protest (Stop Climate Genocide), with the founder of the campaign group, Marcus Calderwood, delivering a speech via a loudspeaker. The protest is loud and disruptive and soon activist leader Marcus is arrested, which Felix points out in his report is the 21st time he has been taken in by the police.
The episode then flashes forward 6 months and Marcus Calderwood is cycling down a quiet country lane on his bike. He is wearing a helmet with a camera on it, and soon a car comes up behind him and starts getting too close and flashing its lights. As Marcus gets nervous and tries to pull over, the car speeds up and hits him, sending him flying off his bike and onto the side of the road, unconscious. The unseen driver of the car then stops, but instead of helping Marcus, they remove his helmet with the camera on it and drive off.
A whole night passes and Marcus is still on the side of the road... he regains consciousness and sees his leg is badly broken, before passing out again. A farmer then spots him and calls the police, but as they arrive he is barely alive. Just as he is being loaded into an ambulance, Marcus tells the paramedic that he knows who hit him and that it was a police officer before giving a name that we don't hear.
We learn later that Marcus died in surgery from a ruptured spleen. Felix meets Grace, the paramedic who looked after Marcus, and she thanks him for meeting her as she doesn't know who else to contact. She explains that she told a police officer, Nick Taylor, at the scene of the crime what Marcus had told her about his killer, but the police are doing nothing about it.
Felix calls a police press officer called Helen and tells her what Grace said, and soon PC Nick Taylor is being called into the station for questioning. Nick is grilled by his boss and he denies hearing what Grace said at the scene of the crime. He is also made to hand over his phone.
The police officer named by Calderwood isn't being revealed and everyone calls him Officer X, but the hunt for him soon goes cold when he isn't at his home and the car allegedly used in the hit and run is missing from the property.
DI Miles Southgate arrives from Hampshire and New Forest as the SIO for the case, along with DS Iain Packham. They take control of a meeting between them and the local team, including Leila Hassoun-Kenny who is the CPS. They reveal Officer X as Justin Mitchell and say there is currently no mobile evidence putting him at the scene of the crime. The suspect's car is also missing and so is the victim's bike, meaning there is no forensics. They do, however, have CCTV footage of the suspect's car boarding a ferry the morning before, and they believe Justin's girlfriend Sandra is driving.
We then meet Sam Malik, a defense lawyer who takes on cases that aren’t very popular in the public eye and has arrived at work after a session with his therapist. His colleague, Claudia Wood, tells him a man has been looking for him, but he seems more interested in getting more tablets from his therapist than taking on new cases.
Meanwhile, the police hold a press conference where reporters are annoyed that they aren't giving much away or naming Officer X - Felix says he knows who the officer in question is, but they ask for him to keep quiet so he doesn't jeopardize the case.
Justin is back to see Sam and he reminds him that they have met before in the courtroom while on different sides of a case. Justin tells Sam that he won the case against the odds and that made him think that if he ever needed a solicitor in the future then he would come to Sam. Justin identifies himself as Officer X and tells Sam that he wants him to represent him.
Nick is questioned by Southgate and Packham and they grill him about a group chat called D4 on his phone. They tell him they know he has wiped incriminating conversations from the chat on his phone, but he plays dumb and refuses to answer any of their questions.
Southgate gets news that Justin has handed himself in and dashes to Sam's office to arrest him. But when he arrives, Sam informs them that Justin has left but promises to be at the police station at 9am the next morning. Sam asks who the CPS is working on the case and when Southgate tells him it is Leila Hassoun-Kenny, his reaction makes it clear they know one another. Once the police have gone, Claudia tells Sam he would be mad to touch this case, but Sam seems keen to take on the challenge.
At home that evening, Sam's son also tells him that he shouldn't take Justin's case on because he doesn't think that he will be able to cope with the pressure of the job.
The following morning Packham fills in Southgate with all the information he has found on Justin and Marcus... but not only do they have a history with lots of former complaints from Marcus against Justin, but also some of the files they need are suspiciously missing from the police system.
After a sleepless night, Sam picks Justin up and they head to the police station. Justin is cocky and confident that he won't be found guilty... adamant that he didn't kill Marcus. When they get to the station, the SGC protestors are outside. Sam offers to go around the back, but Justin wants to face the crown and barges his way through, leaving Sam to follow in his wake.
Inside Justin is rude to Southgate, telling him he thinks he's soft, but Southgate arrests him on suspicion of causing death by dangerous driving, while Leila and Sam catch up with plenty of banter.
Sam talks to Justin before the police get to him, asking him where he was when Marcus was killed. He claims he was on a run, without his phone, and doesn't seem to be taking the whole thing very seriously.
Justin admits that he knew Marcus and talks about their past meetings where they had crosswords, including a time when Justin stopped Marcus on his bike for using his phone.
Eventually, Sam gets the truth out of Justin about why there is animosity between him and Marcus as he recalls an incident where he'd attended a car crash where he tried to save the life of a pregnant woman, but she died because the ambulance couldn't get there in time after being held up by one of Marcus's SCG protests that was blocking a road. Sam points out that because he blames Marcus for the woman's death, the police have a motive, but Justin maintains that he still doesn't know why Marcus named him just before he died.
Reporter Felix goes to see the SCG group, who are now moving into Marcus's house after he left it to them in his Will to become a center for the cause. His neighbour makes it clear he doesn't want them there, but the new group leader tells him to leave.
Justin gets questioned by Southgate and Packham but he spins a complicated and bizarre story about his girlfriend Sandra driving to Serbia to get a new dog, and also stopping on the journey to get her car fixed by a distant uncle in Slovenia who is a mechanic after she clipped her car in the gym car park. It is clear that no one believes his story and Southgate is getting more irritated by the minute so ends the interview.
That night in his cell, Justin asks one of the female officers for a fancy breakfast the next morning, and as she agrees it is clear that he is highly regarded at work by some. He asks her if the group chat was deleted and she nods.
The next morning Southgate is back at work and talks to Leila about Sam, and she reveals that Sam's wife took her own life by jumping in front of a train. Packham then interrupts by telling them he has found a video of when Justin pulled Marcus over for using his phone while riding a bike... the headcam footage sees Justin threatening Marcus with knocking him off his bike and leaving him to die on the side of the road, the exact same thing that actually happened to him.
Sam goes to meet Justin and is fuming... telling him they now have evidence of him threatening Marcus with a crime that has not only happened but one for which he has been identified by the victim as the suspect. Sam asks if there is anything else that Justin isn't telling him before they go to court, just as the credits roll...
All five episodes of Showtrial season 2 are now available on BBC iPlayer. The series will also air on Sundays at 9pm on BBC One.