'Falling Skies' has delivered some impressive season 4 content in the past few weeks, including that casting announcement of Mira Sorvino atop the full-length trailer from New York Comic-Con, though a few questions remain unanswered. Now that the main characters are out on the road and increasingly divided, what will become of season 3 guest stars Robert Sean Leonard or Noah Wyle's former 'ER' co-star Gloria Reuben?

A few months earlier, TVLine confirmed that former 'House' star Leonard would reprise his fan-favored role as Dr. Roger Kadar for at least one episode of the 2014 season, which itself expanded to 12 episodes total. And while Leonard's character seemed poised for a recurring presence, it seems Gloria Reuben's exclusion from the recent trailer as resistance aide Marina Peralta proves no accident. According to a recent report, "At this time, there are no plans for the ER alum to return as Marina."

On the plus side at least, the recent trailer confirmed that fellow season 3 guest star Megan Danso would return as Ben Mason's resistance fighter friend Deni, having been excluded from the end of 'Falling Skies' season 3 for time and scheduling.

Along with the news of ‘Falling Skies’ season 4 expansion and Mira Sorvino, the TNT drama has also added Treva Etienne, who will play a new addition to the resistance, Dingaan Botha. So far, we know that new showrunner David Eick has plotted multiple separations of the core characters, potentially revealing the alien Espheni’s true intentions for invading Earth in the process. Eick also revealed that the season would draw inspiration from 'The Empire Strikes Back' in telling parallel stories for its separated cast.

Check out the 'Falling Skies' season 4 trailer again below, and tell us in the comments what characters you'd want to see return when the new episodes pick up in summer 2014!

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