A yacht is tracked by police as an organized crime gang uses it to smuggle deadly weapons into Britain and a recording of a prison phone call helps jail a bank cashier for arranging to steal an elderly couple's life savings.

A discarded cigarette butt gives police the proof they need to find the murderers of a young father shot and killed in broad daylight. A used match found in a drainpipe identifies a arsonist who burnt a 400-year-old building to the ground.

An airport hire car provides the clues to the identities of a pair of South African hitmen who have come to the UK to brutally murder a private investigator in his home. A rare bottle of Caribbean rum helps convict a prolific burglar.

A train ticket and a chance encounter help hunt down a pair of hi-tech international fraudsters with links to the Russian underworld. A glass milk bottle gives police the evidence that seals a case against a violent offender.

A bloodstained shopping trolley holds the key to solving the case of a vicious assault. A distinctive pair of curtains, seen on a video call thousands of miles away, helps put a phone thief behind bars.

A drug boss is put behind bars thanks to a paper trail from his dodgy property empire. A bank cashier helps convict a fraudster who's posing as a police officer, exploiting a vulnerable pensioner in a scam to extort thousands of pounds.

A fingerprint from an old break-in solves a murder at the same factory months later. Elsewhere, a DNA spray means police can finally apprehend a prolific motorbike thief.

A hotel guest book gives police the names of an international drug smuggling network, and thieves who stole £20,000 of food from a factory are caught out by a car number plate.

A fingerprint on a fish and chips wrapper places a gunman in a rural location miles from his home, and a man’s laptop reveals that he is behind a luxury gift card fraud.

A jacket recovered from a suspect’s home has the DNA of two stabbing victims on it, and a fingerprint on a getaway car number plate snares an armed robber.

Fingerprints found after a break-in and brutal beating are enough to convict a man of murder, and crooks who burgled a man's home and started using his credit card are caught by CCTV.

Blood spatters found on a trench coat belonging to a suspect in an unrelated case of armed robbery links a callous killer to the murder of a wealthy pensioner.

A few spots of the victim’s blood on a blue shirt convict a murderer, and a rapper incriminates himself when videos he posts online about his drug dealing are seen by the police.

A blood-spattered hammer is the key to charging the prime suspect in a murder case, and a drug gang is brought down when one detective focuses on how the product is packaged.

A USB stick with information about illegal drugs is found at a respectable businesswoman’s house, and police crack down on the conversion of guns designed to fire blanks.

A single piece of paper found on top of a hidden fax machine gives police the number of a shipping container used to smuggle millions of pounds' worth of drugs from Thailand.

A hammer contaminated with the DNA of both victim and killer helps police solve a murder investigation, and a burglar is caught after photographing himself at the crime scene.

A man is linked to a series of murders by a shoelace with his final victim’s DNA on it, and coded information in a spreadsheet reveals the perpetrator of a campaign of blackmail.

An ice pick is recovered from the roof of a pub and brings a murderer to justice, and an anonymous letter throws suspicion on a man who may be storing and manufacturing guns.

A car hidden deep within a scrapper’s yard unlocks the riddle of a suspected gangland shooting, and police secure the UK's first conviction for modern day slavery at a car wash.

A few specks of grey paint help to solve two brutal axe murders, and a bungling burglar is caught when his DNA is found on a rock used to smash a window at one of his break-ins.

A jacket left behind in a stolen car carries the DNA to prove who was driving the vehicle. And a witness gives police key evidence from 30 years ago to crack a cold-case murder.

A reclusive millionaire is found murdered in his home in west London, and police find hundreds of thousands of pounds in cash still there.

A fatal house fire turns suspicious two years on when it emerges the victim was visited by a stranger the night his home was destroyed. Will a plane ticket give a moment of proof?

When a child goes missing, police have few leads. They have a suspect but not enough evidence to prove anything. Eventually, a torn-up cheque gives them their moment of proof.

An organised crime gang supplying large quantities of drugs are almost impossible to uncover. But painstaking surveillance leads police to the kingpin, bringing down the operation.

Two people die in an arson attack on their home, but police can’t get a DNA profile from matches left at the scene. Then, an eagle-eyed detective clocks a problem with the CCTV.

When a missing woman is found dead, family and friends raise suspicions about her boyfriend. But police need hard evidence that he was involved. And they eventually get it.

Two men heading to a business meeting are kidnapped and forced to transfer a large amount of company money. Police unpick a web of calls and CCTV to find their moment of proof.

Police suspect foul play after a meet-up goes wrong. But it takes toxicology tests to reveal the deadly cocktail that convicts a killer.

Police are left confounded by a serial burglar’s Houdini-style disappearing act. But a single piece of information brings their game of hide-and-seek to a sudden end.

Two young women are shot dead in Birmingham on New Year’s Eve. But it takes an audacious undercover mission for police to infiltrate rival gangs and find the moment of proof.

When the search for a missing woman becomes a murder investigation, a baseball cap and DNA on a discarded beer can help detectives find her killer.