Eclipse's ex-lover returns; Reed and Sage find alarming information about Lauren's new friend; Thunderbird helps Blink open up about her past; Jace approves a special surveillance program.

Dr. Campbell attends an anti-mutant summit, attempting to take the Hound program national, and some of the team at Mutant HQ goes on a dangerous mission to stop his efforts.

Polaris' baby begins to suffer from a deadly illness, leaving the Inner Circle unable to heal her, and prompting them to turn to an unexpected source for help. Meanwhile, Reed and Lauren take an excursion to deliver illegal meds, but Reed's powers complicate their plans. Then, Thunderbird and Blink meet the leader of the Morlocks - a shadowy group of mutants that live underground - who offers to help them find the Inner Circle, but the two factions may not have the same goals.

The Mutant Underground wrestles with the idea of recruiting the Inner Circle to assist them. Andy considers reconnecting with his family when he learns about his father's powers, but Lauren may not be as willing to have him back as their parents. Find out if the Mutant Underground and Inner Circle will be able to put their differences aside in order to save John from the Purifiers.