Sean Campbell

Walter worries about Peter after observing Massive Dynamic's assembly of the doomsday device; an intense investigation begins after a dead body is discovered.

The Author aligns with Gold, while Emma, her parents, Hook and Regina try to stop them; Henry steps up to save his family.

The agents' investigation into the government's knowledge of extraterrestrial life puts them in danger; Scully is forced to trust a mysterious man.

A decapitated medic may be an evolutionary freak capable of regeneration.

Not everything is as it seems.

During an off-world mission, Ronon (Jason Momoa) is ambushed and captured by his former friend, Tyre (Mark Dacascos), and turned over to the Wraith. As the team scrambles for leads to locate their friend, Ronon undergoes a torturous ordeal.