Red vs. Blue Season 5 Episode 10 The Nesting Theory ( Air Date 2007-01-05 ) Genre Animation, Comedy, Sci-Fi & Fantasy category. Overview "Grif and Simmons decide to enter the cave. Meanwhile, Tex is firing at the Blues to try and deduce who is being possessed by O'Malley. Church starts to suspect that Sheila is possessed by O'Malley, causing her malfunction. Tex notices Sister, and reacts jealously.".