Robert Sean Leonard & Gloria Reuben Join ‘Falling Skies’ Season 3

The former "House" and "ER" co-stars sign up for recurring roles in the new season.

Blair Marnellby Blair Marnell

During the closing minutes of "Falling Skies" season 2, Tom Mason (Noah Wyle) and the 2ND Mass prepared to leave Charleston and continue the fight against the alien Overlords… until a new alien race made its presence known. Although it's unclear if the new race will side with humanity, the latest "Falling Skies" news suggests that the 2ND Mass may be staying in Charleston despite their intent to hit the road.

Deadline is reporting that Robert Sean Leonard and Gloria Reuben have both signed on for five episode arcs on "Falling Skies" season 3. Leonard will portray Roger Kadar, PhD; an eccentric and obsessive genius who runs the power grid in Charleston and lives underground with his pet rats… which leads the children of the city to refer to him as "The Rat King."

Above ground, Reuben will play Marina Perlata, an "extremely intelligent" and politically knowledgeable women who acts as Tom's aide; which seems to suggest that Tom may take a leadership role in Charleston despite turning down an offer from Arthur Manchester (Terry O'Quinn) to run the provisional government in the finale.

Reuben and Wyle were once co-stars on the long running medical drama, "ER;" however, Reuben has also appeared in "The Flash," "Homicide: Life on the Street," "The Agency," "Law & Order: Special Victims Unit" and "Numb3rs."

Leonard is widely known for playing Dr. James Wilson for eight seasons on "House," in addition to his appearances  in Dead Poets Society, Much Ado About Nothing and Much Ado About Nothing as well as several Broadway and theatrical roles.

"Falling Skies" season 3 is expected to debut on TNT in Summer 2013.