Big Jim and Julia form a tentative alliance to search for proof that will discredit Christine, which leads them to new information about the Dome's capabilities. Meanwhile, when tensions run high in town and threaten Christine's leadership, she puts a plan in play that has deadly consequences.

As the world outside the Dome is rocked by a catastrophic meteor shower, unexpected alliances form inside the barrier. Eva tries to indoctrinate Barbie deeper into The Kinship and Big Jim and Julia turn to one another while isolated on Bird Island outside of town. Also, Joe is forced to accept help from Sam, the man who killed his sister.