As Barbie descends further into the mysterious tunnel in hope of finding Sam, he comes across a world filled with unanswered questions.

Barbie turns to his father for help contacting Julia but realizes that he may not be trustworthy; Big Jim declares himself sheriff of Chester's Mill.

Barbie is apprehended by mysterious men and relentlessly interrogated about the Dome; Big Jim forms a deal that could permanently seal the fate of the Chester's Mill residents.

The latest threat intensifies, leaving Chester's Mill residents at risk of being crushed to death; Melanie's health declines as the egg's fate remains uncertain.

Barbie investigates Ben's claim that something strange is going on in Chester's Mill, but Eva surprises him with unexpected news. Meanwhile, Norrie and Hunter grow closer, and Christine advises Joe to move on.