Sierra Dawn Thomas

It's an epic showdown as two legends set their sights on one another. Also, two castaways attempt to put their past behind them and start a new game while another castaway introduces the "spy shack" 2.0.

The merge brings another twist in the game that leaves two castaways out of the celebratory feast.

The 30th season will feature the first-time theme of "Worlds Apart," with castaways divided into the three separate tribes, White Collar, Blue Collar and No Collar. Minutes into the game, castaways are forced to choose between honesty or deception, and one castaway becomes ill after trying to satisfy his need for protein.

Tribes drop their buffs in a switch that will shake up alliances. Also, one castaway struggles after receiving a blow to the head, and another castaway's desire to flex his power in the game could be his greatest weakness.

Survivors drop their buffs for a tribe swap, and the game starts from scratch for one set of castaways. Also, one castaway leaves his tribemates stranded in the ocean so he can search their camp for the immunity idol.

Emotions run high when the game begins to take a toll on one tribe, and castaways try to pull their way to safety at a physical immunity challenge.