In the fourth episode, Professor Marcus du Sautoy concludes his investigation into the history of mathematics with a look at some of the great unsolved problems that confronted mathematicians in the 20th century. After exploring Georg Cantor's work on infinity and Henri Poincare's work on chaos theory, he sees how mathematics was itself thrown into chaos by the discoveries of Kurt Godel and Paul Cohen, before completing his journey by considering some unsolved problems of maths today, including the Riemann Hypothesis.

Over 133 years in the making, from humble beginnings manufacturing 'Hanufuda' cards came one of the world's most recognized videogame companies, from the birth of Mario and Luigi to Donkey Kong and Zelda... to beating its competition and presenting itself as a platform for quality games and strong values. This is the story of Nintendo.

With optional Hebrew subtitles. Simon Schama explores the history of the Jewish experience from ancient times to the present day. This programme begins the tale 3,000 years ago, with the emergence of a tribal people in a contested land and their extraordinary book, the Hebrew Bible, a chronicle of their stormy relationship with a faceless, formless, jealous God. It was loyalty to this 'God of Words' that defined the distinct identity of the ancient Jews and preserved it despite all that history could throw their way". The story unfolds with a dazzling cast of historical characters: Sigmund Freud dying in exile in London; Victorian evangelicals and explorers following 'in the footsteps' of Moses; Jewish mercenaries living, prospering and intermarrying in the pagan land of Egypt; Messianic Jews dreaming of the Apocalypse; and a Jewish historian, Josephus, who witnessed first-hand the moment when the apocalypse finally came and the Romans destroyed the Jewish High Temple in Jerusalem.

Lil Hughes Knipp recalls meeting Father Maskell near his end... and knowing that he would never be charged. The search for Brother Bob and a potential killer begins, and the revelation of a potential suspect named Edgar Davidson comes forward with an interesting story.
With more people coming forward, more suspects appear including a man named Billy Schmidt who lived in Cathy’s apartment. A contact from one of Cathy’s sisters could give new insight on the case.

Arguably the most powerful painting about war ever achieved. It portrays the slaughter of civilians after Napoleonic troops entered Madrid in 1808. The programme reveals the historical truths behind the painting and shows exactly how Goya achieved this masterpiece of protest. he painting's content, presentation, and emotional force secure its status as a groundbreaking, archetypal image of the horrors of war. Although it draws on many sources from both high and popular art, The Third of May 1808 marks a clear break from convention. Diverging from the traditions of Christian art and traditional depictions of war, it has no distinct precedent, and is acknowledged as one of the first paintings of the modern era.
According to the art historian Kenneth Clark, The Third of May 1808 is 'the first great picture which can be called revolutionary in every sense of the word, in style, in subject, and in intention'. Discover how Goya used drawings by authentic witnesses to depict a real firing squad.

What connects amateur sleuths turning up at crime scenes, anti-social behaviour in schools and riots? Marianna Spring has spent one year investigating harmful behaviour on TikTok spilling out into the real-world. As well as crunching the numbers, Marianna tracks down TikTok users, victims and former employees to interrogate and expose how extremely high engagement on TikTok around particular topics appears to be creating these 'frenzies'.
The documentary explores how users go to extreme lengths in order to get more engagement in a battle for followers and likes. Marianna investigates the role TikTok's algorithm and format plays in what’s happening and reveals insiders’ concerns about the app. The film seeks to find out if this is the real danger and what impact it is having on society.