In this episode, we see how a family are left distraught when two of their dogs are stolen from the 'secure' garden. The family launch a massive social media appeal in a desperate attempt to find their two cocker spaniels.

They're not alone, with more than a thousand dog thefts reported every year. Most of these pets are never recovered, but a unique DNA database has been created in an attempt to reverse that trend and reunite more animals with rightful owners.

Also in this episode, narrated by Rav Wilding, how laser-scanning technology is helping CSIs create 3D digital crime scenes in meticulous detail.

In this episode, a train driver suffers facial injuries after a brick is hurled at his cab, shattering the window. The train was travelling at 70mph, but the driver manages to bring it safely to a standstill, despite his injuries.

A rise in the number of incidents like this has prompted one train company to start installing on-board technology aimed at making journeys safer for passengers and staff. The new features being unveiled include laser-imaging technology to scan the track and embankments – the same technology Nasa used to map the surface of the moon.

The programme, narrated by Rav Wilding, also looks at how victims of domestic abuse and stalking are being issued with forensic-marking sprays in a trial aimed at keeping women safe.