Police: Suspect No.1

Gangs are flooding Norwich with drugs brought in across the county borders. Hunting the head of the gang, a specialist team gather evidence and make an arrest - but is it the right man?

In this first episode, shop workers are left terrified when two men, one armed with a meat cleaver, the other with a kitchen knife, launch separate violent crime sprees robbing store tills for quick wads of cash. Humberside Police must now find both perpetrators before they strike again.

In Grimsby, CCTV shows a man bursting into a busy shop armed with a meat cleaver. But with his hood pulled down over his face detectives must now uncover his identify. DC Andy Taylor and DS Ryan Johnson investigate a theory that the suspect could live nearby. It's vital they find the clothing worn in the robbery and then link it to their emerging number one suspect.

In Hull, another man, making no attempt to hide his identity, robs a Post Office armed with a large kitchen knife - and prepared to use it. Police quickly link him to other recent violent robberies. But with no fixed address, how do they trace him? When news of a possible sighting comes in PC Hannah Saleh acts fast.

Detectives finally sit eye to eye with each suspect in separate interview rooms. Have the police found enough evidence? Will the cases stand up? Will the suspects walk, or face the full force of the law? It's down to tough questioning and nerves of steel.

In Kingston upon Hull, innocent victims are terrorised in their own home by a knife-wielding intruder. Humberside Police must identify and track this dangerous suspect and bring him to justice.

As the investigation gains momentum, there is an unbelievable turn of events - less than 24 hours later, the same victims are targeted again, but this time by two attackers, and left traumatised. Detective Constable Heather Butler must build a strong case to put these hardened criminals behind bars once and for all.

During an in-depth investigation, incriminating evidence is found, including a razor-sharp meat cleaver left behind at the crime scene. But as the case unfolds the connection between the two attackers stuns detectives.

Time is of the essence for Humberside Detectives. As the suspects finally face detectives in the interview room, will damning evidence allow police to play them off against one another? And will this result in an imminent confession?

In Grimsby, a work night out turns ugly as two visiting businessmen are left with serious facial injuries after being assaulted in a pub. Police arrive, and while attempting to make an arrest, a large crowd of bystanders violently intervene, assaulting the outnumbered officers. As back up arrives, the situation escalates.

A main culprit is identified and arrested but claims self-defence in the pub brawl. Two other suspects are taken in for their part in attacking police in the street disturbance.

It's a race against the custody clock as Humberside Detectives try to separate the truth from the lies. Can CCTV footage help them challenge the suspects' version of events? And how will the suspects respond when challenged in the interview room?

Detectives are determined to secure justice for the victims, one of whom has been left with life-altering injuries. But will they be able to secure strong evidence to fight the suspects' denial and counter claims or will they be forced to release the suspects?