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.

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.

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.

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.

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.

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.

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

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.

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.

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.

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 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.

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.

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.

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.