Four strangers' lives collide at an immigration detention centre: a woman escaping a cult, a refugee, a father leaving a job, and a bureaucrat on the verge of scandal.

Ambitious bureaucrat Clare Kowitz arrives at Barton as the new General Manager and is struck by the extent of the facility's dysfunction. Ameer finally makes it to Australia only to discover tragic news awaits him.

Clare's relentless hunt for the leak in Barton pays off, while Cam wrestles with his conscience over the beaten detainee. Sofie uncovers an ambitious escape plan, and Mina tries to support her grief-stricken father.

Tensions run high as Clare struggles to keep control of Barton. Sofie's mental health deteriorates as the memory of what Gordon did to her is resurrected. Ameer's lies come undone, putting his visa chances in severe jeopardy.

Margot makes an important discovery that leads her to believe that Sofie is imprisoned at Barton. Clare cuts a deal with Ameer that will change his and Mina's futures. While Cam faces the repercussions of his past decisions.