The Crash Detectives are called in to investigate a hit-and-run that leaves a cyclist fighting for her life, while mystery surrounds the death of a delivery driver on a busy dual carriageway.

When calls start coming in to report debris on the M4 motorway, police discover that a father and son have been in a serious crash. As traffic chaos builds, the pressure’s on for the collision team to find out why the car left the road.

When a Friday evening trip out in the car ends in a fatal crash, the driver refuses to accept his driving is to blame. The collision team must find the evidence to prove the real story of the night.

When a head-on crash leaves a grandfather dead, Chris discovers the answers could lie in electronic data within the car. As his mission to access it begins, he unearths an intriguing story of what really led up to the crash.

The collision team are called in to investigate a high-speed crash on the M4 which closes the motorway in both directions. With a driver under arrest and offering few clues, the answers could lie with a silent witness.

A pedestrian is seriously injured after being struck by a car in a residential street, but police are suspicious of the teenaged driver’s version of events. After a motorcycle crash outside a busy garden centre, the full story is revealed - by the bike itself.

It’s Friday night, and desperate 999 calls start flooding in to report a car travelling the wrong way along the motorway - but it still ends in tragedy. A motorbike and van collide in a busy city centre, but the story isn’t as clear as it first seems.

When a woman dies after being hit by a lorry on her way to play bingo, the team must reconstruct the scene of the crash to find out who’s to blame. A cyclist fights for his life after a crash with an articulated lorry.