Season 4

Mark battles enemies new and old in his fight to keep Earth safe.

Loyalties are challenged when an old enemy is revealed.

Consequences weigh on Mark. Oliver takes on a new job.

Hurm.

Mark embarks on a new and dangerous mission, throwing Debbie into a tailspin and plunging Eve into uncertainty.

Family bonds are put to the test. Under pressure, Allen makes a new friend.

Nothing goes according to plan during a massive confrontation.

Mark confronts his darkest fears as his life changes forever.