Between the LinesEpisodes Guide

Ambitious Chief Inspector Tony Clark is head of CID at Mulberry Street police station and has applied for a transfer to the Flying Squad as a Superintendent. After a low-level drug dealer exposes corruption, Clark's office is "locked down" and he discovers that his transfer has been approved – but it's to the Complaints Investigation Bureau – which is not what he wanted.

Armed police have shot and killed an apparently armed youth, and Clark is running the investigation. The press make the most of the event to stir up unrest, the investigation is being hindered, and tensions rise, not least between Clark and his new boss, John Deakin.

A white WPC is alleging sexual assault by a black sergeant, however it appears that there is a hidden agenda. Meanwhile, Clark is in difficulty with his first disciplinary case as his main witness is missing.

The investigation into an assault of a prostitute by CID officers has reached a dead end, Clark's personal life is getting more complicated and pressure from Deakin is not helping. The assault case seems to be cracked from an unusual quarter, but with the only eyewitness dead, it seems there's only one way out.

Mike Carswell wins his appeal against conviction for murder but did corrupt officers conspire to convict him? Meanwhile, Mo is undercover investigating missing property and Dunning is looking to move upwards, out of the Met. A major witness in the Carswell investigation, however, turns out to be too close to Clark for comfort.

Clark and his team visit Liverpool to investigate an armed robbery conviction. A confession may have been beaten out of the robber, and a local reporter has an axe to grind.

Tensions rise on a picket line leaving Clark to discover who is responsible for serious injuries. Hard evidence is in short supply and old loyalties muddy the waters. Meanwhile, Clark's personal life is heading rapidly downhill.

A youth stabs Constable Norton to death and Clark's leave is cancelled to investigate an outstanding complaint against him. Was Norton the saint he is portrayed as or can Clark uncover a different picture?

Clark and his team investigate an officer who is caught apparently accepting a bribe but must discover whether he's been set up. Meanwhile, officers involved in the Carswell case, including Jenny Dean, are feeling under pressure. Clark has a suspect in the corruption case but politics intervene.

When Customs and Excise stage an observation on suspected drugs dealers on the Thames, one of their number, Fisher, goes missing. Huxtable asks Clark to investigate. Relations between all the different parties involved complicate the enquiry. Customs and Excise are convinced Thames Division is collaborating with the drugs squad to sabotage their operation.

Joey Pearce, a young man, is found hanging in his cell at St. Helen's nick. The arresting officer, DI Gordon, is called to help revive the boy, but he is dead. Clark is called out and starts investigating; one by one Clark interviews everyone in the custody suite. Pearce had been arrested with another man, Dilly, a known dealer, in possession of dealer quantities of crack.

Supt. Urquhart is arrested around the back of King's Cross Station with a prostitute in his car. Commander Huxtable is pleased; rumours about Urquhart's relationship with porn king Denis Ralston go back years. Urquhart's home is raided, and it is clear to Clark that he is running his life on more than a Super's salary.

Deputy Chief Constable Dunning has been suspended following allegations made by Billy Urquhart. At Jenny Dean's funeral Clark is rebuffed by her father. Deakin tells Huxtable that he has been sent home on leave pending the Dunning investigation and that he should take some time off himself.

Clark is called to investigate the failure of a uniformed constable to arrest a violent racist; it transpires that this is a Special Branch undercover officer, but it isn't clear whether he still has the interests of the law as a priority. Meanwhile, Deakin is on trial and Clark's rival, Graves, is up for promotion. The visit of an American revisionist historian, Deakin's acquittal and Graves's promotion all cause headaches for Clark.

Det. Supt. Lindsay has confessed to killing his wife, claiming he did so as a crime of passion; however Clark is sceptical. His suspicions are aroused because of similarities to a case Lindsay investigated five years ago, and as time is running out, he is under pressure to get the right result. It is discovered that Lindsay had been having an affair with his sister-in law, and the post-mortem uncovers crucial evidence.

An armed response team is called to the robbery of an off-licence, and one of the robbers is shot dead. Clark, called in to investigate, is given a tape, which indicates that the police have given the robber a gun in exchange for drugs. However, the tape is incomplete and Clark's team must track down the original - but, when it is found, the truth is revealed.

A government minister with an axe to grind against the Met is caught In flagrante delicto with his secretary; it is suspected that his movements have been leaked to the press by one of his protection officers, and CIB launch an investigation, if only to clear themselves. Clark is given the case, but it turns out that it may be more political in-fighting than police corruption.

Special Branch, watching a T.A. centre, witness a potential raid on its weapons store; armed officers shoot a 68-year-old workman by mistake. The intruders claim to be working for MI5 and refuse to assist Clark's investigation. It transpires that MI5 were bugging the centre to entrap a junior officer and a Special Branch Inspector suspected of selling arms to terrorists. After a number of machinations, the official position turns out to be a whitewash, and Clark learns that the tentacles of the security services reach into his activities.

Mounted police go in to break up a riot following a demo against public spending cuts; a young girl is injured and later dies. Clark must find out who authorised the police action, and discovers that Chief Superintendent Tattersall, although accepting responsibility, may be covering up for failures in the chain of command.

Bosher, an investigative journalist, prints details of a "royal conversation" allegedly from a tape leaked from GCHQ; when the tape is reported missing, Clark investigates whether Special Branch stole it. Angela Berridge, however, says that the tape has never existed, and this is confirmed by her contact at GCHQ. Mo discovers that MI5 have a plant in the newspaper office and persuades him to dig into Bosher's files; it is found that Bosher has fabricated the story and claimed £20,000 to pay for the non-existent tape, which enables Mo to persuade him to print material to discredit the local Chief Constable and assist ACC Jan Lewis' search for social and sexual justice.

To his surprise, an armed robber is convicted, and confesses to other robberies, for one of which Peter Hoskins has already been sentenced to eighteen years. This raises doubts about the methods of Detective Chief Superintendent Trevor Dunn; Hoskins has made a complaint, which lands on Clark's desk. Commander Sparrow pressurises Clark to achieve a quick result, while Hoskins claims to have a videotape of Dunn accepting a bribe. The tape has supposedly been left in a railway station locker and Clark must find it. The tape is found, but Clark finds Naylor trying to remove it to protect Dunn, and it seems that the locker key was not in Hoskins' possession. Meanwhile, it turns out that Sparrow has recently visited Hoskins in prison.

Following a vice squad celebration, P.C. Curles knocks over a young boy; chased by Supt. Cullen, a traffic officer, he evades him, changes back into his uniform and returns to the scene, pretending to assist. The car he was driving turns out to be unregistered and, finding only a blank police memo pad in it, Maureen has little to go on. The boy's parents complain and Clark is called in to investigate. The hit and run victim dies, and Clark discovers an ongoing feud between traffic police and the vice squad; evidence of the accident initially points to the wrong officer, but eventually Curles is interviewed. However, since he assisted at the scene, his fingerprints are all over the car.

Uniformed officers called to a sudden death are accused of stealing property; a local burglar eventually confesses to the crime, but Clark is not sure that he hasn't been coached into an admission. Naylor's boss is seen reporting to Deakin, and Naylor is given extra wages as a "bonus"- or bribe. The following day, Graves suspends Naylor and initiates disciplinary proceedings. Clark traces events back to Deakin and confronts him about the inoperative alarm and burglary of a solicitor's office, which Mo finds has not been reported. After leverage has been applied in the right places, Naylor's job is safe. However, there is a deniable link between Angela Berridge and Deakin.

Declan Harris is found murdered in Epping Forest, with evidence claiming he's been forced into being a Special Branch informer. Clark is tasked with investigating the suspicion that the Branch also killed him. Meanwhile, Naylor has been transferred and takes up an existing murder investigation; his boss, however, is all too keen to get it wrapped up without delay. It transpires that Harris had recently contacted Inspector Dilke, who has him down as a fantasist. Deakin is seen talking to Trevor Bull, an extremely violent armed robber, and Clark is under pressure to get a quick- and convenient- result. Harry's principal suspect in the murder is Simon Bridge, the victim's nephew.

Clark, Naylor and Dilke attend Harris's funeral, as does Trevor Bull. The official report has exonerated Special Branch of Harris' death and Clark is told to back-pedal on Deakin. It turns out that Deakin has funded works at Bull's house, and Clark puts this to Bull seeking the dirt on Deakin, to no avail. Instead of going to Mo's promotion party, Clark goes round to a safe house to see Angela Berridge, only to find Deakin there. He is told that Deakin has been freelancing for MI5 and if he goes down, so will Angela. Bull meanwhile has dug up a pump-action shotgun and has shot a police officer who came to investigate. Ignorant of Bull's actions, Deakin blackmails Clark into "fixing" him but after Clark has left, realises he may need assistance.

Having sacrificed his career in the Met, Clark ponders what to do next, until Deakin pays him a visit - and asks him to travel to Tunisia to help a tabloid newspaper substantiate a story about an MP's private life.

Naylor struggles to regain his composure following the death of his wife. Meanwhile, Connell's career in the Met hangs in the balance, and Clark accepts his first investigation after delving into the world of espionage.

Deakin asks Naylor and Clark to track down a missing person.

Connell calls upon Clark and Naylor for help after falling into difficulty with a client.

Clark takes on the task of providing protection for a Chilean general, who has been receiving death threats.

Connell goes undercover to find out who is setting fire to a chain of fur shops, while Clark fears for Naylor's safety after he accepts a job working for a dodgy pharmaceutical company.

Clark investigates when a computer engineer from the defence industry is found dead in his garage, and ignores Deakin's warning to steer clear of the investigation.

Clark and Naylor set up a profitable arms job, but Connell wants in on the action - but the pair are convinced that it's too dangerous.

Clark is asked by Deakin to go undercover as a gun runner for a major neo-fascist rally in Belgium, posing as a right-wing arms dealer.

Clark and Naylor are blamed for failing to stop an arms shipment heading for Northern Ireland, but realise that they have been double crossed when Connell reveals she is still working for the police - and has offered up her two former colleagues for a promotion. Trapped on a boat that is about to implode, will Clark and Naylor make it out alive?