GateWorld has received the first story details for “Outsiders,” an upcoming episode of Stargate Atlantis now in pre-production and set to air in the second half of Season Five.

Written by Alan McCullough, the episode is expected to go before cameras in July, just after the crew’s mid-season hiatus. “Outsiders” features the return of Paul McGillion as Dr. Carson Beckett.

In the wake of Michael‘s use of the Hoffan drug to taint the Wraith‘s food supply (“The Kindred”), Dr. Carson Beckett and the Atlantis expedition have resettled the Balarans, a group of human survivors, on another populated world. The locals have welcomed these “outsiders,” including a woman named Novo and a man named Sefaris, with open arms. Some of them have become like family. But now the Wraith are coming for them.

These men and women have been made immune to Wraith feeding by the drug, but they are also a threat. Any Wraith who tries to feed on them will be instantly killed (“Poisoning the Well”).

Elson, Jervis, Renni, and the other councilors who serve as village leaders debate the fate of the outsiders. If they do not surrender the people they have given shelter, their entire village is at risk of destruction. Colonel Sheppard enters the council chamber as they are considering the problem, and offers them another option: Rather than hand over their guests, his team can help resettle everyone on another world, in relative safety from the Wraith — more than 600 people.

Convinced that the Wraith might kill them either way, Elson agrees to the evacuation. A small contingent of Wraith guard the gate, and Sheppard’s team prepares to attack them. In the window of time before the Wraith hive ship arrives, they believe they will be able to get everyone through the Stargate. But it may be easier said than done — and not everyone on the planet wants to leave their home.

With the lives of two peoples at stake, the Atlantis team may find that they are the real outsiders.

Guest characters include Carson Beckett (Paul McGillion), Novo, Sefaris, Elson, Jervis, Renni, several Wraith, and guards.

Learn more about the new season of Atlantis in GateWorld’s episode guide! Season Five premieres July 11 on SCI FI Channel in the United States.