Here's an interview with star Jason Ritter. There are more interviews with additional cast members at the link. >> E! Online. The following spoilers below come from these interviews.
"They're doing something next door you do not want to see," star Sarah Roemer (Leila) told me with a look of shock and horror, while taking a break from filming episode 10. "I don't even think there is one word that I can say about it because it is that big."
Big, but it involves the wee little ones. We'll have to wait until episode 10 to find out (for the first time in my set-visit history, our cameras were not allowed to shoot any of the scene—it was that hush-hush!), but we can only assume that Sarah's character Leila is finally reconnecting with her abducted sister, Sam...right? And perhaps something truly terrible is being done to her and other children? Gah!
"Episodes seven through 10 have taken a whole new turn," a similarly wide-eyed Jason Ritter tells me. "Once Hal Holbrook gets in here we start to learn a little bit more about his character and what he's doing and where Leila's sister is. It's just a whole different thing, and I had no idea. I thought that Sam had disappeared, and they would figure it out later—you know, we'll find her, and 'Oh, she was just hiding in the bathroom.' But it's a whole intense storyline and that's exciting."
When I begged Clifton Collins Jr. (the seemingly evil and fully creeptastic Thomas) to stay away from the kiddos on the stage next door, he just said with a laugh, "It's the stage moms and dads you should be concerned about. I'm good with kids."
The picture below is a page that was recovered from Michael Buchanan's notebook which consists of a number of names and "codes" or an encrypted passage below that.