Police believe someone broke into their home that night and a fire was started, but no-one has ever been charged.

With claims of evidence compromised, mistakes made and missed opportunities. We turn our attention to the crime scene forensics.

Hear from people closest to the case, speaking for the first time about their concerns.

Written and produced by Gabby Colenso

A BBC Essex production for BBC Sounds.

Police get a breakthrough when something was found dumped near the Shakoor family home, eleven days after the fatal house fire.

The discovery means the fire is now officially a murder investigation.

As enquiries increase there's a problem, which could provide a reason why this case remains unsolved.

Written and produced by Gabby Colenso

A BBC Essex production for BBC Sounds.

The town of Harlow is in shock after a house fire left Dr Sabah Usmani and her four children dead.

A fifth child is on life support in hospital. The father, Abdul Shakoor, is by his daughter's bedside praying for her to pull through.

As the community in Essex tries to come to terms with what’s happened, detectives reveal the Shakoor's home wasn’t the only fire in the street that night and the search for answers begins.

Written and produced by Gabby Colenso

A BBC Essex production for BBC Sounds.

A normally quiet residential street in Harlow is woken in the middle of the night to screams for help.

What Adbul didn't know then is that he’ll be the only family member to survive and also that someone else may have been in the house.

Written and produced by Gabby Colenso

A BBC Essex production for BBC Sounds.

A father is the sole survivor of a house fire that killed his wife and five children.

On 15 October 2012, Dr Abdul Shakoor jumped from an upstairs window of his house in Harlow, Essex. It was a desperate attempt to get help.

His wife Dr Sabah Usmani and their five children died in the fire and police opened a murder investigation.

Dr Shakoor has been fighting for answers and justice ever since.

Written and produced by Gabby Colenso

A BBC Essex production for BBC Sounds.

A top bullion dealer explains how the toilet could have disappeared and where the gold might be today.

Meanwhile, Jimmy Sheen’s pocketed £520,000 from the gold sale and an investigation shows he’s made big money from other crimes.

Explore where his missing millions could be and whether they will ever be in the hands of the police.

Presenter: Clodagh Stenson.

A trial begins and the three defendants plead not guilty.

Details emerge about reconnaissance trips to Blenheim made days before the heist.

Also, Jimmy Sheen’s voice notes are shared. They offer a rare chance to eavesdrop on the crime as it’s happening, uncovering how he cashed in on his golden loot.

Presenter: Clodagh Stenson.

Image: Getty

Four years later a toilet thief is unmasked as James ‘Jimmy’ Sheen.

An investigation uncovers Sheen's dark past leading up to the Blenheim burglary with a career of crime that began in his twenties.

The ringleader of multiple gangs, he's tied to violent thefts, nationwide fraud and a shooting in Coventry.

Presenter: Clodagh Stenson.

Image: Getty

As the palace reopens to the public, curious visitors flock to witness the infamous crime scene. Behind the scenes, Blenheim’s Chief Executive scrambles to tighten palace security.

An internationally renowned art hunter is hired by the insurers to hunt the golden treasure. Meanwhile playful sightings of fake golden toilets pop up across Oxfordshire.

Presenter: Clodagh Stenson.

Image: Getty.

Stunned Blenheim Palace staff are coming to terms with an early morning raid as the gang make their getaway with the £5 million gold toilet.

Meanwhile, rumours swirl about who could have orchestrated the heist with fingers pointing to the toilet’s creator, Maurizio Cattelan, who has a history of elaborate stunts.

When the artist shares a statement denying any involvement a police investigation is launched and the hunt for the real robbers begins.

Presenter: Clodagh Stenson.

Image: Getty.