Citizenfour received the Academy Award for Best Documentary Feature at the 2015 Oscars. The film was directed by Laura Poitras concerning Edward Snowden and the NSA spying scandal." In January 2013, Laura Poitras received an encrypted e-mail from a stranger who called himself Citizen Four. In it, he offered her inside information about illegal wiretapping practices of the NSA and other intelligence agencies. Poitras had already been working for several years on a film about monitoring programs in the US, the result of the September 11 attacks. In June 2013, accompanied by investigative journalist Glenn Greenwald and The Guardian intelligence reporter Ewen MacAskill, she went to Hong Kong with her camera for the first meeting with the stranger, who identified himself as Edward Snowden. Several other meetings followed. The recordings gained from the meetings form the basis of the film.

Follow actor William Shatner through interviews with the other actors who have portrayed starship Enterprise captains in five other incarnations of the Star Trek franchise. Shatner's subjects discuss their lives and careers before, during and after their tenure with Star Trek. With the use of conversations and archival footage, they explore the pressures, stigmas and sacrifices that accompanied their roles and their larger careers. During the process of the film and with help from the other Captains, Sir Patrick Stewart, Avery Brooks, Kate Mulgrew, Scott Bakula and Chris Pine, Shatner overcomes his disdain and learns to embrace his best known character, Captain James T. Kirk.

This episode discusses the human exploration of Antarctica, in particular the mission led by Captain Robert Falcon Scott, whose team died on the way back from the South Pole. It shows the scientific work in the modern human bases in Antarctica, especially Mawson Base and its observation of Adelie Penguins (partially through tracking devices). The second half of the episode describes how the series was made. Most crucial was of course the camera work. To get access to the wildlife of the sea, for example, boats, divers, suspended capsules and remotely controlled cameras mounted on inflatables were used. Particularly dangerous to divers were Leopard Seals and other predators. The film concludes that although working in Antarctica is now much easier than during the early days of exploration, human footsteps on the continent are still exceedingly rare in part because of international treaties prohibiting industrial exploitation.

'The Coldest War': With the polar ice caps shrinking due to global warming, new trade routes are being exposed, along with billions of dollars' worth of natural-resource reserves. The five nations bordering the Arctic are readying themselves to fight for it. The problem is that there's one non-NATO country that already considers itself rightful owner of the region: Russia. With Vladimir Putin's recent military annexation of Crimea, there's a definite possibility its aggressions will boil over, returning the international community to precarious Cold War footing. We will head north to witness NATO forces participating in the largest polar military exercise in history. 'Heroin Warfare': Since the U.S. occupation of Afghanistan, heroin production in the region has skyrocketed, making the country the number-one producer by a large margin. Though Iran, Afghanistan's neighbor, is an ultraconservative country, Afghan heroin flowing across the border has actually caused Iran to have the worst heroin use problem in the world. Suroosh Alvi gets a rare look inside Iran to meet the suffering heroin addicts, and see how the country is coping with the illegal drug trade.

Technology is evolving from an external tool we wield when needed to an always-there presence that is with us, on us, even inside of us. As we become more and more wired, are we becoming digital devices ourselves? In this episode meet a Swedish mom who implanted an RFID chip as a lifestyle choice; a filmmaker who lost his eye in a gun accident and replaced it with a camera; and the so-called "world most connected man," who uses between 300-700 tracking and life logging systems to monitor every aspect of his life.

A group of brave individuals risk their lives to save the last of the world's mountain gorillas; in the midst of renewed civil war and a scramble for Congo's natural resources." Virunga National Park in the Congo is a place of unique natural beauty. It is the home to a plethora of wonderful animals and vegetation but as is so often the way, it has several serious problems that threaten it. It's the location of human violence, corruption and exploitation. The disasters that specifically loom are two different groups, the M23 and SOCO International. The former are a violent rebel force who engages in an ongoing civil war with the Congolese government and the latter are a British energy company who specialise in oil exploration. Both M23 and SOCO invade the park in their own ways and neither seems very interested in the laws that have been set up to protect the flora and fauna that exist there, far less the people who live there. It seems hardly surprising in the case of M23, as they are a paramilitary organisation who can hardly be expected to be concerned with such things but it is the more legitimate big business SOCO who seem more worrying if anything. We discover in fact that they have been involved in a bribery campaign, utilising M23 as enforcers. It's a very murky situation where big money walks all over an impoverished nation and disregards a natural space that they can see no value in in their pursuit of financial profit.