Sitting on top of the world's biggest patch of oil, the extended family that runs Saudi Arabia has managed to fend off the assaults of modernity and democracy since the state's foundation.

The episode follows Galster and his men as they mastermind a sting to catch a prominent Korean animal dealer, discover a dead tigress in a sadistic snare, and secretly film traders selling tiger bones and teeth in a Myanmar market.

Virtually unknown in the West and full of sinister complexities, it's a tale of multi-million dollar scams involving corrupt judges and bureaucrats, bent policemen, fake lawyers, mafia henchmen, and a cast of hapless victims who are either dead or reduced to poverty.

Following three stories - an independent women, a migrant worker desperate for a wife, and a local police unit fighting to stem the recent spate of kidnapped wives - the episode investigates a problem that could spell major trouble for China in the future.

Filmed before and during the Israeli re-occupation of the Gaza Strip, the story follows Mahmoud and the hospital staff as they cope with gun battles between Palestinian groups, the reality of life under the Hamas Government, and the collapse of the ceasefire with Israel that ushered in the bloodiest period the region has seen in years.

Judges, journalists and civilian plane-spotters provide pieces of a puzzle that suggests the CIA has a secret programme of kidnapping citizens and transporting them abroad to be tortured or put before what even US military lawyers call "kangaroo courts".

Mark Franchetti gives a candid profile of former KGB agent Andrei Lugovoi, who sparked the biggest diplomatic crisis since the Cold War when he became Scotland Yard's prime suspect in the poisoning of Alexander Litvinenko in 2006.

As he prepares to stand in this week's Russian parliamentary elections, the investigation takes places the Litvinenko murder mystery in the context of a newly resurgent Russia, where Lugovoi is regarded by many as a hero.

Early on the morning of 16 April 2007, 23-year-old student Seung-Hui Cho opened fire on the Virginia Tech campus in America, killing 32 people and wounding 25 others before turning the gun on himself.

In the lead up to the first anniversary of that tragic day, the episode interviews key witnesses in an attempt to understand what might have caused Cho, a young man with no criminal history, to plan and carry out mass murder.

John Sweeney travels more than 5,000 miles through the old Soviet Union, from Joseph Stalin's birthplace in Georgia to a former labour camp in Russia, to investigate whether the dictator's reputation is being rehabilitated despite the fact he was one of the 20th century's most notorious mass murderers.

Geert Wilders, who was known as one of the most controversial of Dutch politician in the Netherlands - the story tracks from campaigning in the elections, meeting members of the anti-Islamic network who back him, and to expose a conspiracy theory promoting the belief that Islam is taking over Europe.

The story traces an extraordinary journey for three young activists from their dreams for a new future to the reality of the Egyptian revolution after one of the Arab world's most brutal and entrenched dictatorships, Hosni Mubarak - who was stepped down as president in 2011.

A decade ago, it became part of the biggest urbanisation project in human history, as the Chinese government decided to take half a billion farmers and turn them into city-dwelling consumers.

Historian John Dickie investigates the story of Italy's elusive powerful crime network and Europe’s biggest cocaine traffickers - 'Ndrangheta', which uncovers inside the secret world of their amazing underground empire.

Clinical Psychologist and addiction expert Professor John Marsden travels to the state capital in Denver, Colorado to investigate the impact of cannabis legalization on a country that already suffering an epidemic of teenage marijuana use.

Dan Snow travels to Congo, seeking to provide some insight into the vast central African country’s history, its colonial legacy, post-independence chaos, and endemic corruption.

[i] Swedish statistician, Professor Hans Rosling presents as 'live' studio event featuring cutting-edge 3D infographics painting a vivid picture of a world that has changed in ways to the people barely understand – often for the better.

He begins his journey in Hanoi before heading into Vietnam’s exotic highlands where, in the aftermath of the war with America, a vast coffee-growing programme was launched to help the country‘s economic recovery – but has led to widespread environmental damage.

With the preparation for the upcoming month of the World Cup 2014 in Brazil, the episode takes place at one of the iconic and exclusive hotel - Rio de Janeiro's Copacabana Palace, which tells the story of the workers and visitors - where it has played host to everyone from its existence.

Pulled from thousands of hours of security footage with more than a hundred cameras, the story takes viewers inside Kenya’s Westgate Shopping Mall as the siege unfolds.

The story follows at Sandy Hook Elementary School in Newtown, Connecticut, where it reveals the perspective of the families of victims and survivors as they rebuild their lives after the shooting events in December 2012.

After the events of Chapo Guzman's arrest in February 2014, the story follows up to explore the various ways on the US government enforcement agencies that have become bound up in the business of Mexico’s notorious Sinaloa Cartel, seemingly in the name of bringing down its kingpins.

[424][j] The episode follows British girls and how they had been attracted and traveled across to Islamic State in Syria - where the radicals were trying to lured them with a mixture of slick marketing, social media and religious fervour.

Swedish statistical showman Professor Hans Rosling returns on-stage, featuring with more holographic-style projection for facts and figures that shows his consideration to put an end from extreme poverty across the world.

Dan Reed uncovers the story on the unseen footage of the massacre at Charlie Hebdo magazine and of the three days of horror that followed, leaving 20 dead and a nation traumatised.

Filmmaker Liviu Tipuriță explores inside the extreme world of Romania's new traditional Gypsy music and contemporary pop, with lyrics that glorify money, fast cars, glamour and bling.

As the UK begin its process for leaving the EU after its referendum results, Katya Adler travels across the European continent examining whether the Union can survive by facing the biggest challenge in its 60-year history.

He meets guerrilla fighters who have pledged to lay down arms, but also discovers a negative consequence of their disarming, as the paramilitary gangs that control the drugs trade grow in power.

[476] The story follows the assassination of the North Korean dictator’s half-brother, Kim Jong-nam - who was attacked at Kuala Lumpur airport in February by using the lethal nerve agent VX.