Bitcoin is the world's leading virtual currency, but unlike real money, it is not backed by a government or properly regulated. Bitcoin is exchanged and held digitally by users - which is attractive to criminals selling drugs, pornography and arms. But now Bitcoin is moving into the mainstream and being openly marketed as an investment opportunity. The film investigates what Bitcoin is and what it means, going inside a Bitcoin mine in Iceland - where currency is made - and spending time with the Bitcoin millionaires of Silicon Valley.
The programme also hears from others who have been scammed out of their life savings and investors who think the cryptocurrency is an enormous scam and that the writing is on the wall. Around the world, authorities are sounding the alarm that Bitcoin is too risky - is it too late, or too crazy, to try to become a Bitcoin millionaire?

April 1453. Sultan Mehmed II unleashes an artillery attack on Constantinople unlike any the world has ever known. It's the largest concentration of cannons that the world had seen in one place. The monumental task of keeping the Ottomans out of Constantinople falls on the shoulders of Genoese soldier of fortune Giovanni Giustiniani. He and his men must defend 14 miles of city walls. Mehmed launches his ambitious plans to break through the walls of Constantinople, but Giustiniani's mercenaries manage to forestall the attacks.

Three years after the devastating fire, Lucy Worsley has exclusive access to the Cathedral of Notre-Dame de Paris at a key turning point of the restoration. Work to rebuild and restore the monument is being ramped up in a bid to meet the ambitious deadline to reopen it to the public in 2024. Scaffolding now fills the interior of the cathedral, giving Lucy and the team unprecedented close-up access to every inch of the structure. Lucy meets scientists, historians and craftspeople working to return the 850-year-old Gothic masterpiece to its former glory.
The fire coated Notre-Dame with tons of toxic lead dust, so specialists are now decontaminating the site. Unique access to the stunning rose windows allows Lucy and the stained-glass historians to uncover the mysteries of these enigmatic 13th-century works of art. An unforeseen legacy of the fire threatens to destroy the remaining vaulting, so the team must develop an ingenious solution to save the stonework. The loss of the roof during the fire reveals hundreds of large iron staples embedded in the stone along the top of the walls. And the incredible task of sourcing and cutting two-thousand perfect oaks gets underway to rebuild the world's most complex medieval timber structure - Notre-Dame's extraordinary roof and spire.

Schwalmstadt Maximum Security Prison in Germany. Locked up behind the walls of this 12th-century castle are 188 of Germany's worst offenders. The prison is a fortress surrounded by a moat, and houses dangerous criminals, many of whom attend intense therapy sessions.

Jennifer Griffith and Sarah Carver were working for the Disability Administration and noticed all this corruption firsthand. They wrote to the Social Security Administration, wrote to lawyers, wrote to the president of the United States. But nothing ever came of their complaints until the Wall Street Journal story broke. Then, with national attention brought to Conn, the Senate, the FBI and the SSA (who’d been enabling the fraud the whole time) finally stepped in.
Series finale. Eric leads the government on a wild goose chase. The fallout from the fraud takes its toll on a struggling Kentucky community.

Vlad Dracula was somewhat successful in having the upper hand during the first five-hour fight in the night attack; however, Mehmed’s army won the battle because of their strength and numbers. Vlad could not kill Mehmed II and fled the scene. After the battle, Mehmed and his army enter Târgoviște which was abandoned by Vlad Dracula. But when he entered the city, Mehmed saw a horrific scene. Muslims were impaled by Vlad in Târgoviște, and there was a ‘forest of corpses.’ In history, this is considered a sad event for the Turks. The experts said that when Mehmed saw these impaled bodies, he immediately started praying. One of the dead bodies was of his father in law Hamza Bay.
Days before, Mara and Gülbahar foiled the Wallachian plot inside the sultan’s harem. Radu Dracula takes the throne in Wallachia on Mehmed II’s orders. Radu Dracula promises his loyalty to the sultan, and Mehmed gives 2,000 men to him. We see a restless king Mehmed II back in Istanbul, because he was not successful in killing Vlad Dracula. However, after 15 years, Vlad’s head is brought to Istanbul by one of Mehmed’s soldiers at the end of the last episode of the series.