The images of brothers Tamerlan and Dzhokhar Tsarnaev are released to the public setting off a violent chain of events. Meanwhile, clues from their past tell a complicated story - how was the radicalization of the ethnically Chechen brothers and the existence of potential collaborators. The post-9/11 biases played a role in the investigation.

The Arctic is the harshest environment on Earth: little food grows, it's dark for months on end, and temperatures stay well below freezing for much of the year. Yet four million people manage to survive here. Human Planet tells remarkable stories of extraordinary people who make their homes in nature's deep freeze. In springtime, Amos and Karl-Frederik set out across the sea ice with their dogs to catch a real-life sea monster: a Greenland shark! Inuit mussel-gatherers venture underneath the sea ice at low tide for a perilous race against time as they gather their food. And the children of Churchill, Manitoba, set out on the most dangerous trick or treating Halloween in the world: they risk coming face-to-face with deadly polar bears on the streets of their town. Who'll get the tastiest snack?

Andrew Graham-Dixon begins his exploration of German art by looking at the rich and often neglected art of the German middle ages and Renaissance. He visits the towering cathedral of Cologne, a place which encapsulates the varied and often contradictory character of German art. In Munch he gets to grips with the earliest paintings of the Northern Renaissance, the woodcuts of Albrecht Durer and the cosmic visions of the painter Albrecht Altdorfer. Andrew also embarks on a tour of the Bavarian countryside, discovering some of the little-known treasures of German limewood sculpture.

Carl Sagan teaches students in a classroom in his childhood home in Brooklyn, New York, which leads into a history of the different mythologies about stars and the gradual revelation of their true nature. In ancient Greece, some philosophers (Aristarchus of Samos, Thales of Miletus, Anaximander, Theodorus of Samos, Empedocles, Democritus) freely pursue scientific knowledge, while others (Plato, Aristotle, and the Pythagoreans) advocate slavery and epistemic secrecy.

Rehearsals briefly resume amid uncertainty over the band's future. Following a productive meeting with Harrison, the Beatles agree to abandon the idea of a live show and relocate to their Apple Corps studio to formally record the new album. Billy Preston, a musician the group met in Hamburg, joins in on the sessions on electric piano.

This widely praised by critics film was created with cooperation from Paul McCartney, Ringo Starr and the widows of John Lennon and George Harrison. Filmmaker Peter Jackson delves into invaluable footage archives to make a film that shows the truth about the Beatles recording together the album Let it Be, which had the working title of Get Back. The production employed film restoration techniques developed for Jackson's previous works on sixty hours of film footage and 150 hours of audio, spending four years in editing the series. The final cut covers 21 days in the studio with the Beatles and climaxes with the full 42-minute rooftop concert.
In part I, the Beatles begin rehearsing at Twickenham Studios for what is at first meant to be a television special about the recording of their next album leading up to a live show at a location to be determined. During the sessions, Paul McCartney and George Harrison play some songs that would later appear on their respective solo albums. After seven days of rehearsals, Harrison abruptly leaves the group.