A convicted murderer who has been studying law inside is given the chance to appeal and chooses to represent himself in court against James Steel - his former prosecutor.

A police officer is killed in a shoot out with a drug dealer. Based on the testimony of another dealer, Brooks and Devlin must determine whether back up was slow to arrive and left the officer to die because he was gay.

The terrifying CCTV image of a toddler being led to his death haunts this episode of Law & Order UK which deals with the difficult and morally complex issue of children who kill. As a society, we are very unforgiving of child killers but if the killers themselves are only children, it begs the question - who really is responsible for the crime? With two children in the frame, each blaming the other, can forensic evidence prove who is guilty of strangling little Conor to death? In an emotionally gut wrenching episode, George defies his superiors and instead takes instruction from the victim's mother who has a surprising point of view on the crime. Can the justice system, and ultimately the government, afford to be lenient?

DS Devlin and DS Brooks investigate the murder of a 13 year-old boy boy, Sean Monroe, the son of a fellow police officer who was killed and put down a storm drain. A note found on the body points to the work of Andrew Dillon, who was sentenced for an earlier racial murder and is serving his sentence. The racial motivation for the killing seems confirmed when a second boy, Dev Desai, is found strangled with the same note in his pocket. However, their investigation leads to a security guard, Marcus Wright, who admits to having encounters with both boys at the shops where he works. He says the boys deaths were God's will and he was simply doing God's work. If Wright is to be believed, it means that Dillon was wrongfully convicted. The case becomes personal when James Steel is accused of having purposely buried a witness statement that would have likely exonerated Dillon. He finds himself in dock but the judge allows him to conduct his own defense.

The team investigate, when mother and carer Lia Brown is killed by a stray bullet,what the involvement is of 12-year-old Kaden Blake in her death. Kaden is caught up in the local gang culture, so keeping silent is his only protection. DS Matt Devlin is drawn to this damaged boy, saddened to see a life so doomed by circumstance, and furious that local dealer and gang leader Mark Ellis remains untouchable by the law.

A drive-by shooting outside the Old Bailey leaves one police officer dead and another wounded in what appears to be a targeted attack on a witness in an attempted murder trial. However, Ronnie and the team are surprised to learn the gunman was specifically targeting police officers, believing his family victims of a police cover-up. The defense team argues their client has been subjected to racism by the police. Can Jake and Alesha convince the jury that the defendant ought to be tried as a murderer and not a victim?