As a second assault on Paris is being prepared, Emperor Charles must make a difficult decision. Meanwhile, in Wessex, Judith must make her own difficult choice.
The populace of Paris is in a panic after the appearance of the Viking fleet, and Emperor Charles, at the behest of his daughter, announces he'll remain in the city.
While Rollo worries about the Seer's prophecy, the Vikings make final preparations for their raid on Paris.
Tragic circumstances greet the fleet on its return to Kattegat; Lagertha is usurped and convinces Ragnar to help her reclaim her title.
An alliance angers Floki; Princess Kwenthrith makes political moves.
As the new Viking settlement prepare for their first harvest, King Ecbert pays them a visit.
A mysterious wanderer arrives in Kattegat; Lagertha and Athelstan establish a Viking settlement.
King Ecbert proposes a deal to the Vikings in the Season 3 premiere. Later, Ragnar leads his forces into battle.
A politician in Prague is framed for murder, triggering the team's effort to take down the Kingmaker, a shifty strategist who's behind the rise of powerful politicians. Meanwhile, Liz unearths a secret that Red has been hiding.moreless
Ragnar's invading party are met with extreme violence when they march on King Ecbert's villa.
Horik and Ragnar travel to Wessex, but their true purpose is disputed. Meanwhile, Princess Aslaug's prepares to give birth.
Justice is dealt to Jarl Borg, and allies are made on both sides of the sea.
Ragnar receives an unexpected offer from King Horik and Lagertha's new husband doesn't seem overly pleased to see her. Meanwhile, Athelstan becomes King Ecbert's trusted aide.
Lagertha is once again reunited with Ragnar and Bjorn make another choice. Meanwhile, Athelstan finds it difficult to define his faith and Aslaug has to accept the consequences of her prophecies.
While Ragnar meets Ecbert in search of a compromise, Rollo must lead his people. Meanwhile, Jarl Borg imposes a strict rule on Kattegat.
While the raids on Wessex continue, Ragnar attempts to rule in the west. Meanwhile, King Ecbert faces a new kind of enemy and Jarl Borg makes his own plans for Kattegat.
Four years have passed and Ragnar leads a new series of raids on England.
Collision with the looming iceberg is inevitable, despite last-minute evasive action by the crew and panic soon spreads throughout the ship. Barnes is given a life-changing gift by Watson andHugh is shocked by Louisa's promise to him. Meanwhile, Jim tracks down his daughter deep below decks and Paolo desperately tries to save his brother. As the Titanic goes down, those few lucky enough to be in a lifeboat can hear the cries of people in the freezing water. Who lives and who dies will be decided in the next few hours.moreless
Barnes finds Watson down in steerage and Annie makes a big impression on Mario. Meanwhile, Paolo makes an impulsive gesture and Mary's improving attitude towards Peter causes an argument with her husband, Jim. After the iceberg hits, the residents of steerage are overtaken by panic when they realise they are locked in. During the dash for lifeboats, Mary's daughter causes alarm when she runs back inside.moreless
Captain Smith causes confusion amongst the crew when he shuffles their duties and Grace is horrified by the mix of people during an Anglican service, up in First Class.When disaster strikes,Second Officer Lightoller is determined to get the passengers to safety, but the Malone family are unable to make it out of steerage.moreless
Looking to escape from a scandal involving his daughter, Georgiana, the Earl of Manton tries to secure passage on the Titanic for his family. Meanwhile, tension is mounting between theEnglish and American crew and Jim Maloney attempts to smuggle his wife and children on board.moreless
The team investigates a producer and his use of the casting couch after a woman who auditioned for a reality show is found in Central Park drugged and with evidence of a sexual assault. Once the case is resolved, however, no one is prepared when a family member of the accused decides to subvert justice by breaking the law himself.moreless
The team battles mistrust and prejudice from all sides when it investigates the abduction of a Romani boy who was last seen on his way home from school.
The detectives go up against a defense attorney whose skilled decimation of their watertight rape case brings the bureau chief to the prosecution table.