The "Good vs. Evil" theme is in full force on Thursday night's episode of "Survivor: Gabon -- Earth's Last Eden," and, according to host Jeff Probst, Sugar and Corinne are battling it out.

"Corinne is having to bite her tongue a lot," Jeff explains. "Every time they vote someone out, they are a member of the jury and determine whether or not you win the game. People have to start placating each other."

Also on this week's episode, the "Survivor" auction ignites an existing rivalry, prompting a heated argument that puts the whole tribe on edge.

"There is a great moment with Randy," Jeff continues. "It shows that you can't predict human nature and you can't change who you are in the middle of a game. For $1 million, Randy doesn't seem to care who he offends."

Catch the 10th episode of "Survivor: Gabon -- Earth's Last Eden" Thursday at 8 p.m. on CBS.