While Marston forces Big Jim to try to find out what Christine has planned, Carolyn recruits Norrie to x-ray Hunter while Junior forces Joe to work for the Kinship.
When it becomes clear that Drill wasn't destroyed along with the rock, Claire and Sean seek out a man who underwent the same experience as Sean 30 years ago.
While Big Jim and Julia join forces against Aktaion and Christine, Christine plots to convert or eliminate those who resist her and her alien influence.
While Christine manipulates the townspeople, Big Jim and Julia learn of a new threat.
After bringing together Drill's "friends," Claire and the FBI learn more about Drill. Meanwhile, Wes brings the recovered object back from Mali and Sean warns that it's calling to him.
Big Jim suspects new residents Eva and Christine of plotting against the town, while the other townspeople try to return to their lives.
While Claire meets with Sean, Wes finds a clue that leads him back to Mali... unaware that it's a trap set by Drill. Meanwhile, Lena grows increasingly nervous watching Minx for any signs that Drill is talking to her again.moreless
Claire and Wes learn where Sean is heading, and try to stop him from setting off a nuclear meltdown. Meanwhile, Minx meets Henry for the first time and gives him instructions for Drill's game.moreless
Sean takes Maria hostage, while Claire and Wes discover what Drill's next target is.
While Drill continues manipulating the children, Claire and Jessup discover that Sean was at the hospital... and is the man in Ms. Bellings' sketch. Meanwhile, the FBI trace the computer breach to Wes' home computer, and Maria receives an unexpected visitor.moreless
FBI Agent Claire Bennigan investigates a six-year-girl who attempted to murder her mother, and soon comes to believe that a mysterious person named Drill is manipulating children into killing their parents. Meanwhile, Defense Department agent Wes Lawrence is summoned to the Sahara Desert to investigate a bizarre fulgurite structure holding a missing F-22 that disappeared 4,000 miles away.moreless
The group copes with the death of one of their own, Nurse Jackson and Dr. Naday take things their relationship to a new level and Dash’s new love interest causes problems.
Kara and Emma make progress in their relationships with their mothers. Meanwhile, when Dash and Mae sneak off to be together, Kenji and Brittany catch them and resort to hiring security guards to keep them apart.moreless
When Emma unexpectedly returns, Leo finds himself feeling guilty about their fight and his betrayal of their relationship. Hunter gets some bad news about his health and other relationships change in one direction or another.moreless
Emma goes home but learns a shocking secret; Jordi mulls breaking the law as a means to an end; Leo and Kara leave the hospital; Hunter gets support from Dash as he faces a risky medical procedure; Nurse Jackson and Dr. Naday try to get a response from Charlie.moreless
A pop star checks in to the hospital, but it upsets the status quo. Meanwhile, love is all around as Kara and Hunter's relationship intensifies; Dr. McAndrew hopes to rekindle his romance with Dr. Grace; Emma and Leo start to reconnect.moreless
A new doctor arrives at Ocean Park after being recommended by Nurse Jackson, but she starts having second thoughts about her decision after observing his methods. Meanwhile, Emma, Dash and Jordi go in search of the ideal gift for the newly awakened Charlie and Kara learns the truth about Hunter.moreless
Nurse Jackson, whose actions have caught up with her, finds support from Kara, Hunter, Jordi and Dash. Meanwhile, Emma meets Leo's friends from home, and one of the kids' circumstances changes dramatically. Nurse Jackson (while on suspension), decides to do what she did before nursing, SINGING!moreless
Leo abandons Emma and Jordi tries to fill the vacancy. Meanwhile, a new patient shocks Kara; Nurse Jackson is desperate to keep Charlie at Ocean Park to the point of crossing a line, a position shared by Dr. McAndrew's ex, Dr. Erin Grace, who is returning after a one year sabbatical. Leo and Jordi fight over Emma.moreless
When details of Charlie's accident are revealed, Nurse Jackson is left with a difficult decision to make if she is to honor a promise she made to Charlie. Meanwhile, Jordi gets an interesting taste of freedom.moreless
Friendships start to form when Jordi starts his treatment; Kara goes back to school for homecoming; Emma attends her first dance; and Leo finds himself in an awkward position.
Jordi and Emma bond, in spite of Leo telling Jordi to stay away from her. Also, Jordi's mother, whom he had said was dead, returns to look after her son.
Leo reacts badly to an unexpected outcome from Jordi's surgery. Meanwhile, Kara's parents work their connections in the hopes of finding a heart for Kara.
As the Dome collapses, Joe, Norrie, and Hunter find a way out. Meanwhile, Big Jim loses someone close to him and tries to make a deal with the Dome.
With the egg gone, the Dome starts contracting, threatening everyone within. Barbie contacts his father and demands the egg, revealing the presence of his half-sister. Meanwhile, Melanie's condition grows worse and Big Jim works with Pauline to create a new painting that will show them the way.moreless
The temperatures inside the Dome plummet and Julia and Barbie go to save the food, while Big Jim looks for fuel to power the generator at the high school. Meanwhile, Melanie begins to suffer and Junior realizes that her health is tied to the egg.moreless
Big Jim is reunited with the wife that he believes is dead, while Barbie and Julia are reunited and realize that the egg is missing. Meanwhile, Joe and Norrie meet Hunter and set out to find the egg, as the temperature beneath the Dome begins to drop.moreless