Episode 4 rounds everything out while simultaneously focusing on his career and the next steps. After a performance tribute to Jamal, Ed and Cherry get good news and reflect on a turbulent year.

After unifying much of Japan, fearsome samurai Oda Nobunaga is dead. His loyal supporter Toyotomi Hideyoshi has launched a coup and seized power for himself. Enraged, powerful General Katsuie has launched his own bid to control the nation.
After defeating Katsuie, Hideyoshi finally ascends to power as the de facto ruler of Japan. Still, Date Masamune, a young daimyo in the north, ignores his missives.

The story of Tilikum, a captive killer whale that has taken the lives of several people , including a top killer whale trainer, underscores the consequences of keeping these powerful animals in captivity, the problems within the sea-park industry, the man's relationship to nature, and how little has been learned about these highly intelligent and sentient mammals.
Tilikum was captured in the northern Atlantic Ocean in 1983 and taken to Sealand of the Pacific, a now-shuttered park near Victoria, British Columbia. Former Sealand trainers interviewed in 'Blackfish' say the park’s female killer whales would aggressively gang up on Tilikum, particularly when they were confined in a 20-foot-by- 30-foot pool overnight.

After ending 120 years of civil war and reunifying Japan under his banner, Toyotomi Hideyoshi, the supreme ruler of Japan, lays dead. In a desperate attempt to protect his dynasty, just before his death, Hideyoshi created a council of five powerful warlords. They are to govern Japan until his young son comes of age. But the power hungry Tokugawa Ieasyu declares war on those who oppose him.

In the last episode, despite disturbing revelations of wrongdoing at Three Mile Island before and after the accident, the utility fights to bring the plant back online. Its Unit 1 had its license temporarily suspended following the incident at Unit 2. Although the citizens of the three counties surrounding the site voted by an overwhelming margin to retire Unit 1 permanently in a non-binding resolution in 1982, it was permitted to resume operations in 1985 following a 4–1 vote by the Nuclear Regulatory Commission.
In 2017, it was announced that operations would cease by 2019 due to financial pressure from cheap natural gas, unless lawmakers stepped in to keep it open. Unit 1 shut down on September 20, 2019.
Billed as the worst nuclear incident in U.S. history, what’s particularly scary here is how close Three Mile Island incident came to becoming a national disaster. Without giving away the whole story, cost-cutting 'solutions' almost cause a catastrophic disaster.

From the frozen poles to the searing deserts, this episode shows how animals have come up with strategies to survive the uneven amounts of sunlight that fall on our planet over the course of a year. The exception is on the equator, where the duration of day and night remain the same throughout the year. Here, this guaranteed sunlight drives the great diversity of life in the tropical jungles.