Squintern Arastoo Vaziri~Pej Vahdat is making his way back to Bones. Vahdat has been absent since his last appearance in Episode 5, "The Bones That Weren't". Via tweeter he revealed that he'd be back before season 6 is over and boasted about the episode in question.
“I am returning to my Bones family tomorrow and I couldn’t be more excited. You guys are gonna love this episode.”