DCI Burnside arrives to investigate a murder which looks like part of a series of male rapes gone too far. Andy Wilson, one of the previous victims remembers something about an angel when he was attacked. Following a statement from taxi driver Steve Sanderson, DC Holmes finds a man matching Sanderson's description on CCTV tapes: his name is Mark Angelis and he works for a courier service with an angel logo. Although DS Boulton arrests Angelis in possession of a knife, he insists it is for self defence against the rapist. DS Stanton visits a profiler at Scotland Yard, and later discovers that taxi driver Sanderson has made a similar statement to Stafford Row station. Stanton and Proctor visit Sanderson's wife, and discover evidence that he is the culprit. They call Burnside to tell him, but he's in the back of a cab - Sanderson's cab...

PC Smith is working undercover as a bodyguard for a South African drug importer named Tony Rourke. Rourke offers Smith a contract to kidnap and torture a senior police officer to find the location of a police informer they need kept quiet. Ordered by SO10's DCI Tasker to remain in place and find out more, Smith comes up with a plan to abduct the officer, who turns out to be Sun Hill's own DCI Meadows. Rourke and his right-hand man Jake begin to doubt Smithy's integrity, and end up executing his plan themselves. With DCI Meadows missing, a massive search is underway, until Smithy convinces Ken Stockley, the informant Rourke and his financier are after, to tell him not only Meadows' location but also the identity of Rourke's mysterious ""money man"" - Lucy Haslock, a City lawyer. SO19 raid the warehouse and recover Meadows, in bad shape but alive.

Northumbria Police arrest one 'Frank Bentley' with a boot full of drugs and a handgun, after a high speed car chase through Newcastle. 'Bentley' and his 'lawyer' Liz McAuley are actually DCI Frank Burnside and DS Liz Rawton on an undercover assignment to investigate corrupt CID officers in Newcastle. Their target is DCI Bonnet, who seems to be in collusion with local gangster Saul Anderson. Despite Burnside being threatened by Anderson, and Rawton's cover nearly being blown when she runs into her cousin Cheryl at a bar, Burnside manages to gain Bonnet's trust. When Bonnet and Burnside meet at a private club, they are shocked when the police raid the place, but manage to escape without being spotted or arrested.

Although they are undercover, Burnside agrees to let Liz Rawton visit her mother. Despite a close shave at a family gathering when her cousin's boyfriend turns out to be an associate of Saul Anderson, Rawton and Burnside survive with their cover intact. Burnside even takes part in a little karaoke! Burnside is not pleased when Customs seize a crateful of guns meant for Anderson that he was supposed to see through. Anderson is not pleased either, and takes Burnside for a little drive. Bonnet and Anderson turn against each other, and Anderson is shot. As Bonnet is about to shoot Burnside as well, armed police arrive and he ends up shooting himself.

Ch. Insp. Conway and a team of Sun Hill officers undergo riot simulation training at the Met's training depot in Hounslow. Meanwhile, DC Glaze goes undercover at the Cockroft Estate to gather evidence of dealing in stolen goods, but discovers more than he bargains for when he discovers two rival familes battling for control of the estate, and which may be stockpiling petrol bombs and weapons for a showdown.

Brownlow attends the funeral service of an old colleague that he used to serve with when he was in 182 squad, but soon finds that old wounds are beginning to reopen themselves as old grudges come to light. When Brownlow's arch enemy becomes drunk and assaults two men at the wake, he uses the opportunity to bring his enemy down once and for all. Little does he know that the entire ex-182 squad is being investigated for insurance fraud by an undercover officer from the Fraud Squad – so Brownlow sets out to find out who framed him and why. Meanwhile, Hollis investigates suspicious events at a crematorium after a number of cars are broken into at the funeral service, suspecting that an insider is tipping off a local robber as to the value of the cars at the service.

Insp. Monroe has trouble dealing with a gang of boy-racers who are harassing and intimidating an elderly couple. When the old man dies after an altercation with the gang, Monroe is urged by Brownlow to show 'zero tolerance' to the youths. PC Smith gets close to a nurse at the St Hughs Nurses Home while investigating reports of a stalker in the area.

Ch. Insp. Conway encounters the ""Sun Hill Angels"" at a function, an escort service which DS Boulton believes is also dealing in drugs. Boulton convinces Conway to help him conduct a sting operation against the Angels, which goes terribly wrong when Conway's 'escort' turns out to be an undercover reporter, conducting her own sting on a senior police officer! To keep the story out of the paper, Boulton and Conway offer the newspaper a chance to be involved in the investigation into Chapman, the owner of the Angels. Reporter Geraldine Sands disappears when she goes to Chapman's house to collect the drugs, but when the police find the house, they find she has the situation well in hand.

PC Sam Harker has infiltrated a group of animal rights activists, thanks to Steve Burton, an old school friend from Liverpool. The group's leader, Ged Mellings, is suspected to be planning some terrorist action. While undercover, Harker takes part in some protests and animal liberation actions, and begins to sympathise with the cause. Despite some misgivings, Harker proves himself to Meddings, and discovers his plan to firebomb a local department store. CID lie in wait and catch the gang planting the bombs, and Harker is distraught to have betrayed his friend Steve.

Deakin is furious when a fourth drug dealer is assaulted in a number of days, a case which Beech was supposed to be investigating. Beech enlists Lennox and the pair are soon lead to a couple of possible suspects, the O'Brien brothers. Meanwhile, Rickman is dealing with a domestic involving the O'Brien's sister, Kelly. Daly informs his friend DI Baines of area drugs about the operation, unaware that Baines is the main man and the O'Brien's boss. Beech then tries to pin corruption charges on DI Baines, keen to get one over on his rival.

PC Jim Carver returns to duty after undergoing treatment for his alcoholism. Unfortunately for him, he is paired with PC Dale Smith and their first case involves alcohol! Attending what first appears to be a racial assault at a post office, Carver uncovers a scam to sell thousands of pounds worth of illegally imported alcohol to off-licenses. Smith and much of the relief don't trust him, and after a Customs raid on a off-license which turns out to be an empty building, Carver must go out on his own (and on his own bicycle!) to find the person behind the scam.

DC Danny Glaze sees a man set alight on the Larkmead Estate, and becomes determined to solve the case. They identify a suspect's car from CCTV tapes, and Insp. Monroe discovers a witness to the incident, a girl named Rochelle, who identifies the suspect, Dominic Mileham in a identity parade. When she suddenly retracts her statement and accuses Danny of paying her to identify Mileham, it seems Mileham and his solicitor father will go free. Danny takes a big risk and convinces Rochelle to wear a wire to prove Mileham's involvement.

Investigating a young boy's disappearance, DC Rod Skase takes a career-ending shortcut when he encourages a witness to implicate a man he considers to be the main suspect.

Beech and Deakin infiltrate a bent, high-stakes poker game, where the dealer, Steve Travis, has been offering drugs as a form of payment in cases where he has lost the game. In order to catch Travis in the act, Deakin disguises himself as an Irish businessman and challenges Travis to an all-or-nothing game, while Beech uses a minor player in the league who owes money to Travis as a coy to making Travis come unstuck. Meanwhile, the Drugs Squad's DI Carter is fazed as Meadows watches over the operation.

Boyden and Worrell arrest a man dealing drugs to schoolchildren, but soon discover that he is the son of a key witness to a case which Beech is desperately trying to close. Beech warns Boyden off as he is desperate to nail long-term enemy Jack Masters , but Boyden has other ideas. After managing to get him off a dealing charge, the suspect then assaults one of Masters' informants, and again Beech manages to get him off; little does he know that he is using the case to clear his name completely.

Boyden has a near miss on patrol when a van in front of him collides with a teenage girl. Her friend is identified by a mall security guard as a shoplifter, and after refusing to give her details, Boyden is shocked to discover the girl is Monroe's daughter Jackie. Boyden supports his boss through the ordeal, drawing on his own recent experience with his daughter Amy. As the relief rumour mill goes into overdrive, Monroe demands harsh action for Jackie to silence the officers claiming she will get off lightly. Monroe gets a reality check as he realises how badly fractured the relationship with his daughter is, and is determined to help her when she later goes missing. When Page finds drugs on Jackie's friend, Brownlow intervenes amidst media pressure about the fatal overdose of a teenage girl from Jackie's school, but has further media pressure to deal with when Jackie's arrest becomes public knowledge.

Worell goes undercover as a prostitute on Barrack Lane after a series of punters are assaulted and robbed, the most recent of which resulted in the punter being sliced across the face with a knife. Worrell gets close to Leanne Gibbs, a former tom who is recently back on the game after quitting rehab. Ackland, however, has a troubled past with Leanne, and resents CID using her again for an undercover operation. Ackland finds herself in too deep and nearly blows Worrell's cover, which agonizes Stanton and Meadows.

When Quinnan and Stamp are attacked on the Jasmine Allen Estate trying to get an overdose victim to hospital, Brownlow organizes a community initiative scheme to earn back the trust of the estate's residents. Quinnan decides to face his demons and prove to the relief he can deal with the youth club, but soon finds himself haunted by the memories of his stabbing. Things get worse when a camera donating to the youth club is stolen, and Quinnan is furious when he is confronted by Mick Glover, recently released just a year after his son stabbed Quinnan on his behalf. Estate backlash is rife when the overdosing girl Quinnan and Stamp tried to get to hospital dies, and Boulton discovers local dealers are giving uncut heroin away to school kids. When Worrell, working at a women's drug groups, finds another teenager overdosing, Brownlow demands action. Boulton launches and ill-fated raid on the prime target, causing Brownlow to order the removal of Quinnan and Worrell.

Boulton investigates the shooting of one of the youths from Quinnan's group. Convinced it is linked to the death of Donna Hunter, he searches the shooting victim's house, and Quinnan is disappointed to learn the girl has been dealing drugs. When Robbie Hunter disappears intent on finding his sister's killers, Quinnan conducts a private investigation, but finds himself attacked when he finds a badly beaten Robbie dying in a church crypt. Smith and Harker find Quinnan's car being joyridden but lose it when yobs on the estate interrupt the chase, but Stamp and McCann find it ablaze on wasteground. Jenny fears her husband has been killed, and while Brownlow reassures her and his troops, uniform believe he is deluded. When Boyden and Hagen find a burnt out body in a factory, the team are left fearing the worse.

Quinnan reels following his rescue and the death of Robbie Hunter the day before. When savings of his sister Donna are reported missing the day of her funeral, the mother of the teenagers discovers Robbie gave Donna the uncut heroin that killed her and stole her savings to get a gun for revenge. With AMIP convinced Robbie killed Hall, identified as the burnt out body discovered by Boyden and Hagen the night before, Boulton and Quinnan put their differences aside to prove AMIP wrong. Convinced Mick Glover is responsible for the murders of Hall and Robbie Hunter, they seek the help of the youth club to nail Boulton for a series of burglaries. Quinnan thinks he's found the evidence to nail Glover for murder, until a shocking turn of events robs them of the result.

Santini tries to convince his lover, Jess Orton, to set him up with some drug dealers – he wants out of Sun Hill, and DS Timpney, his friend in Area Drugs, has promised him a place in the squad if Santini can get him evidence on them. However, before he has the chance, the Ortons' club is firebombed, and Santini is shocked when one of the officers assigned by AMIP to investigate the explosion is his old nemesis, DS Rosie Fox. Fox is convinced that Santini is linked to the events in question, but her AMIP DCI, Richard Pallister, believes otherwise. When Santini manages to locate Jess Orton, he persuades her to make a false confession to bombing the club in order to gain the trust of the suspected drug dealers.

Santini is determined to find out if Jess Orton has grassed on him, and when he breaks into her home to challenge her, he causes her to fatally fall down the stairs. Fox is ordered off the case by DCI Pallister and warned that if her actions directly resulted in her death, then she could be facing criminal charges. Vicky plugs DS Timpney for information, suspicious that Santini may not be telling the whole truth. Desperate to conceal his involvement with the Ortons, Santini and Fox find themselves captured by Sherman and Ferguson, and facing possible execution. Fox believes she has a confession for Orton's murder and is attacked by Santini, but after their rescue, it's Santini's girlfriend Hagen who nails him for the murder.

Santini goes on trial at the Old Bailey accused of the murder of Jessica Orton, but tries to talk to CIB and implicate Quinnan and Rawton. A prison guard tells Santini that Sherman's drugs charges are being dropped in favour of conspiracy to murder Santini and Fox, who turns up dead in her hotel room after an apparent suicide. With Ferguson executed and Timpney taken on side by Sherman's heavies, Santini's trial starts falling apart. Hagen is discredited by her Sun Hill colleagues when she lies under oath and breaks down in the witness box after being caught out. With Santini found not guilty, he is warned by his recently released cellmate that he is in grave danger from Sherman's heavies.

Hagen goes undercover as the driver for a manager of a chain of massage parlours, Allison Spencer. Suspected of running a prostitution racket for her uncle and old adversary of Meadows, Charlie Mayne, and the DCI is intent on having Mayne extradited from Portugal. Hagen, subject to gossip from her colleagues over her performance at Santini's trial, struggles to get in with Spencer until Hagen saves her from an ambush. Peter Van Reissen, Spencer's boss and contact for her uncle, asks Spencer and Hagen to rob diamonds from a luxury house. When Van Reissen discovers the man who accompanied Spencer and Hagen to the heist is an undercover cop, Hagen takes drastic action to save his life. When Meadows reveals to Hagen that Van Reissen is going to double cross Mayne, an arrest team is scrambled to arrest all the targets as Mayne flies into the country.

DC Mickey Webb arrives for his first night shift at Sun Hill, and assists an under strength uniform to track down dangerous prison escapee, Craig Ronson, who has served 8 years of life sentence for armed robbery and murder. Ackland warns the newer members of the relief that Ronson assaulted several officers when he was arrested in 1992. With Quinnan and Smith injured in separate mishaps, Ackland attends a break-in at a local sports complex and is confronted with an armed man who tries to attack her with a sledge hammer. Webb arrives and finds it to be Ronson's brother Colin, and uses his arrest to gain information as to Ronson's whereabouts. When Harker goes missing during a door-to-door on the Jasmine Allen, Rickman arrives to find him badly beaten – and herself confronted by an angry Ronson.