After having been seen arguing with her boyfriend in an alleyway a young woman is found badly beaten up. When the team look into the case they find her personal life very complex and it complicates the investigation.

After a night out a couple return home to find their daughter missing and the story offered by the nanny ends up being unreliable.

The baby girl's body is found and the nanny's boyfriend look like the guilty party. After being questioned though Sam and Jacob find themselves with a new suspect.

After a teenager is found dead following house party the main suspects are soon revealed to be a couple of his class mates.

Heaton hold a press conference as he attempts to get a confession out of the prime suspects in the case. When the truth is finally revealed Heaton is shocked.

A body of a murdered woman is found in a park. It is soon discovered that the body belongs to a woman who has been missing since 1988 and her family are informed. Heaton seems the similarities in the crime to a murder case he worked on 20 years ago.

With CID hitting a brick wall in the investigation to the death of Susan Clark, Heaton interviews jailed murderer Ian Ellis. When another missing person is revealed, Heaton arrests him for Clark's murder. When the third body is found, Ellis goes on hunger strike and dismisses his solicitor, leading Heaton to come under fire.

Ian Ellis is rushed to hospital following a suicide attempt in his cell, and things only go worse for Heaton when Banksy discovers Ellis was in custody when the third victim went missing, leading Ellis' family to call for Heaton’s job. He promises Ellis a quick release as he recovers in hospital, but Heaton offers to speed up the process if he gives information on two contractors that could be responsible. One is cleared, but the other is hunted down. After a chase, a woman is found unconscious but alive in his van, and Heaton considers using this to open up the suspect's wife.

Smithy finds a taxi driver beaten up and his takings missing. An Oyster Card belonging to Ellie Gladstone is found nearby and she is questioned about the attack. As the case develops another suspect is uncovered.

Nate and Ben investigate a break in at the home of Jill Bentley and learn that that her teenage daughter, Sarah, was home alone. Ben discovers that Sarah was holding a party at the time. After her boyfriend is found beaten up, Sarah admits there was a party and that Aubrey Haynes persuaded her to take drugs and then tried to attack her.

Maria Joseph visits Nate at work to return the handcuffs he left at her house after they spent the night together. He is not happy though when he finds out that she tends to Aisha Katri's wounds at the hospital and did not get her to report being attacked to the police. As they argue Maria informs Nate that Aisha and her family are illegal immigrants.

PCs Millie Brown and Mel Ryder come across a group of Polish teens hassling a burger seller whilst out on patrol. Pawel is arrested and DS Max Carter interrogates him and finds out he is the nephew of Marek, who runs a local extortion racket. When Carter discovers his latest operation he sets up a sting to bring him down and he asks Pawel's stepmother Julie, to help with it.

CID's raid goes pear shaped after the disappearance of Marek Jankowski, and the shooting of informant Cezar Sobiesneki. Cezar's niece, Marek's sister in law Julie, accompanies him to hospital where he dies. Julie blames Carter for Cezar's death, and things get worse when Carter lets slip he killed her husband. When Marek attempts to abduct Julie's son Lukas, Carter convinces her to help him find her other son Pavel, prime suspect for Cezar's shooting, before CO19 do.

As Carter, Dasari and Banks are trying to catch a drug dealer his accomplice injures a young woman as he tries to escape. The team are determined to find out his identity.

Sally and Ben investigate a theft at a local social club. Magician Drake Danvers' gambling problems make him a prime suspect. When his girfriend is attacked, Drake admits that he is being blackmailed by somebody.

Some drugs are found at a local boxing club following an attempted suicide. The police have a hard time getting the truth out of anyone at the club. Beth and Terry finally come to some some of understanding. Beth finally receives the letter from Witness Protection she has been waiting for but it would mean leaving Sun Hill for good.

Beth and Nate discover a woman lying unconscious at the bottom of her stairs after they are called out to a domestic incident. It is revealed she is married to the owner of the boxing club, Charlie. Charlie insists that his wife just fell. Later their daughter is arrested for stealing money from her father's shop. Beth kisses Nate goodbye.

Art Minshull is found unconscious injured in a layby. Smithy thinks the lorry he was driving has been hijacked for the cigarettes it was carrying. CTV footage shows Art and woman and a child getting into the back of the lorry though. Art will not tell the police the identity of the people who seem to have been smuggled into the country but does admit he was attacked.

After Callum and Leon investigate a burglary they are called to say the missing goods have been returned. Connor Deegan admits his guilt and when his flat is searched by the police his sister is discovered beaten up there. It is she revealed that she is the the real thief and commited the crime to help pay for her drug habit. Connor agrees to help the police catch local drug dealer Darren Bailey.

Sally and Millie attend a domestic disturbance at a house. Larry is throwing his girlfriend out who is a former drug addict as he believes she is using drugs again. When Larry's daughter later disappears he believes that his ex girlfriend is involved.

Sgt Stone, called to the scene of a reported theft, realises that the suspect is the victim of domestic violence. She alerts Stone to a meeting between her husband and his criminal associates, so TDC Fletcher and DS Carter mount a surveillance operation.

Nate Roberts is assigned as the Safer Schools Officer at Deansgate School after investigating a case of arson there. When he and Smithy investigate a fight in a local park, Smithy ends up being stabbed. Nate is determined to catch the guilty culprit as Smithy recovers in hospital.

Nate has to investigate drugs being taken at Deansgate School after a pupil is taken to hospital after taking ecstasy. Everything is not as it seems though as he investigates the case.

When Rhys Tanner's home is broken into Nate investigates. Nate discovers that two school pupils could be involved and investigates further.

Nate has to break up a fight between two parents at the school. Nate later finds out that one of them has become slandered in a rape case. After he is beaten up CID investigate and are shocked to discover the identity of the real culprit.