Survivor Season 21 Episode 6 (Survivor s21e06) with title “Worst Case Scenario” aired on Wednesday, October 20th 2010 at 08:00 pm via CBS Network.
Here is summary for Survivor Season 21 Episode 6 :

One of the game’s most prominent masterminds targets two foes and sets a plan in motion to oust one of them, along with an immunity idol, in one of the most memorable tribal councils of the season.