Most of the previous games have had an obvious theme and a more subtle "real theme". Minority rule seemed to be about psychology and guessing how people will vote, but it was actually about using teamwork to eliminate psychology from the equation. Contraband seemed to be about out-guessing your opponent, but was actually about loyalty, the interests of the individual versus those of the team. The fourth round seems to be about convincing people that you're normal so they'll make contact with you, but it will actually turn out to be about sacrifice.