In the 10th episode (mid-season finale), victory proves costly in the battle between the Vikings and the French as Ragnar squares off against Rollo, sealing the fates of the two brothers.
As they near Paris, the Vikings relaunch their boats, but this time they bear interesting structures made by Floki; Aethelwulf and Alfred arrive in Rome, where honors are bestowed by Pope Leo IV, but in Wessex, relations are less than cordial between King Ecbert and a disgruntled King Aelle.moreless
Holden and his crew find themselves in the middle of a desperate battle when mysterious warships attack and board the Donnager; at the same time, Miller is in the middle of pursuing the Julie Mao investigation when his partner Havelock goes missing.moreless
Holden and the crew slowly start to turn on one another after they are taken prisoner aboard the Martian navy flagship the Donnager. Elsewhere, Miller deals with rioters on Ceres; and Avasarala engages in a nasty game of politics with an old friend.moreless
While Noah and Quentin target Renautas with their new ally, Miko tries to recover her father's sword. Meanwhile, Carlos finds an ally in his quest to fill the role of El Vengador, and Agent Cutler goes after Tommy.moreless
Malina and her mentor travel south from the Arctic Circle to save the world. Meanwhile, Quentin and Noah find an unlikely ally to help them get into Renautas, Miko and Ren arrive in America, and Joanne discovers Luke's s secret.moreless
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.
Chris's addiction problems come to a head when a simple call puts Dov and Chris in the center of an iffy home invasion inquiry. When the victim's secrets surface, Chris and Dov end up in a struggle for their lives.moreless
An infant is reported stolen. Moretti tracks the kidnapper, only to make a bizarre discovery. Elsewhere, Pierce and Moretti probe a related murder, and Donnie sets out to buy a house in the suburbs.moreless
A notable neuroscientist is found dead, and Pierce and Moretti must determine how the killer infiltrated the victim's impenetrable study to commit the deadly deed. Meanwhile, Pierce's father moves in with Pierce and Lewicki.moreless
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.
Moretti questions why Pierce is working a case without her after he accepts an invitation from a renowned environmental activist. The case involves a chain of abnormal neurological reactions, but Pierce's examination of the group of young girls involved uncovers a dark secret.moreless
Donnie doubts Pierce's theory about inattentional blindness as it relates to a series of bizarre public murders. But Pierce has a way to prove his point so they move quickly to piece together the clues and outsmart the clever killer before he can murder again.moreless
October 16, 1864. A double murder keeps Corcoran and O'Brien busy which, as they sift through the evidence, looks like a case of revenge. With tensions high, the citizens of Five Points assemble to watch the exhibition fight between Jasper and "Irish" Jake. There's a lot riding on the fight and Robert Morehouse will be forced to make a serious decision. As Annie continues on her path to try Elizabeth's patience, there may be only one choice to reform the wayward child.moreless
October 11, 1864. Maguire and O'Brien discover a gang's plan to rob the patrons at an upscale fundraiser. It's up to Corcoran to insure the guests' safety without interfering with Norbert Morehouse and Elizabeth Haverford. O'Brien and Corcoran are taken aback when Maguire lets them know about a life-changing decision he's made. Marcus trains Jasper for an exhibition fight against "Irish" Jake McGinnis, but it's apparent to Matthew that Marcus is only concerned with how it benefits himself.moreless
September 21, 1864. A person from Detective Corcoran's past may have information about the loss of his family. When the man after Annie sends in Pinkerton men, Corcoran devises a plan for her safety. Uptown, Morehouse helps his father in his desire to purchase the entire Five Points.moreless
September 17, 1864. In New York City's notoriously crooked Five Points neighborhood, Irish-American Detective Kevin Corcoran of the New York City Metropolitan Police Department's Sixth Precinct finds himself investigating the murder of a young girl that hits uncomfortably close to home. Along with Detectives Francis Maguire and Andrew O'Brien, they navigate the slums of Five Points and the mansions of Uptown to search for the child's killer. Assisted by Dr. Freeman's modern scientific methods of deduction, Corcoran tracks down the killer.moreless
Adam is given the opportunity to see what his life could have been like if he hadn't lost his temper towards an old boss.
When problems arise between Erica and Ryan, after Erica goes to a party with Ethan, while Ryan is supposedly away, Erica is sent back to relive an unusual love affair of her university days, in order to understand her feelings about Ryan in the present.moreless