Police called to do a welfare check on a missing man end up hunting for a double murderer. And an officer on his day off spots a car he knows belongs to a disqualified driver. His investigation not only catches a serial driving offender but a man with a whole load of Class A drugs.

A one-off burglary puts police on the trail of a gang stealing luxury cars to order – and in search of an international fugitive. And when a bank worker is approached on social media, it rings alarm bells and helps bring down a major fraudster and identity thief.

A doorstep distraction burglary leads officers to a violent serial offender. And police cracking down on drug crime uncover a huge fake ID factory serving criminals across the UK.

A seemingly accidental house fire leads detectives to snare a killer. And a van pulled over for having a cracked windscreen turns out to contain a massive cannabis stash.

A suspicious bag handover leads investigators to expose a major money-laundering gang. And police called to a road accident soon realise they're dealing with a case of murder.

What looks like a devastating burglary of family heirlooms proves to be a sham and exposes the so-called victim as a million-pound fraudster. And when police stop a suspicious-looking car on a hunch, they end up bringing down an unscrupulous drug dealer.

A car that fails to stop for police turns out to be behind a life-threatening hit-and-run. And a single fake cheque is spotted by a sharp-eyed bank worker and puts investigators on the trail of a gang of con artists.

When an off-duty officer sees a small drug deal, it leads police to a huge cannabis farm. And a case of car clocking triggers a battle of wits between a cop and a serial crook.

A 999 call about a possible intruder puts police on the trail of a violent attacker. And a traffic stop on the other side of Europe helps police in Bristol solve a burglary crime wave much closer to home.

Neighbourhood cops searching for a stolen motorbike discover a massive stash of cocaine from a major Ecuadorian drugs cartel. And when a police investigator gets a report of a threatening phone call, it leads to her jailing a serial stalker responsible for harassing dozens of women.

What starts with reports of a speeding motorist ends with detectives jailing an aggressive drink driver, who ploughed into another car, killing two innocent people. And a tip-off about an illegal gun in a family home in County Durham helps police uncover a vast haul of dangerous weapons.

What looks like a one-off break-in turns out to be a long-term plot to steal regularly from an elderly woman. And a beat officer finds himself taking a murder confession.

A rookie officer who helps a drunk man get home suddenly finds himself on the front line of a murder investigation. And shoddy building work helps convict a serial fraudster.

A suspicious financial transaction leads police to jail a prolific romance fraudster. And when a spate of break-ins prove to be linked, it ends with an alarming high-speed chase.

An accidental explosion in a Liverpool house ends up exposing a major drugs gang. And the theft of cash from an ATM leads detectives to a pair of serial fraudsters.