Twenty-eight excited Challenge competitors arrive in exotic Thailand and learn that they will be competing in a brand new Challenge -- The Ruins, where the players will be broken up into two teams: the Champions and the Challengers, while competing for their share of $300,000 to be banked in their own individual bank accounts. One trouble-making player causes chaos for his team when he tries to throw the first challenge. Later, two men and two women enter the Ruins, where they must fight for survival.

Teamwork becomes essential at the "Swing On By" challenge, where one player injures herself in an unexpected way and is forced to leave the game with a medical emergency. When both teams conspire to pit two best friends against each other in the "Shadow Fighter" Ruins, chaos erupts and the house is turned upside down forever.

The Champions wonder if their rogue player, Wes, is genuine when he approaches them with a peace treaty. Demoralized from back-to-back losses, the Challengers vow to take home a victory at the "Repo Race" challenge. Two players' spots in the game are extinguished during the "Burnout" Ruins. An unlikely romance is sparked between two Champions.

When Katie discovers a dirty plunger in her bed, she goes ballistic in her hunt for the prankster. A longstanding feud between Champions Tonya and Veronica meets a shocking end. One team's hopes for a win go down in flames at the "Burning Bridges" challenge, when a careless player blows it for their entire team.

Wes makes a drastic move when he senses that his girlfriend, KellyAnne, is getting too close to her ex-boyfriend, Cohutta. A crafty competitor manages to escape being voted into the "Spool" Ruins, while another is completely blindsided by her team's decision.

Controversial Champion Johnny realizes that his biggest hurdle in the game is himself. Veronica is rattled when she learns of Susie and Johanna's plot to send her into the Ruins for the rest of the game. The teams fight for sweet victory at the "Fruits of Your Labor" challenge.

Brad becomes increasingly frustrated with his team's losing streak and hopes to lead his team to victory at the "Rotary Club" challenge. A Champion makes a deal with his teammates that could keep him out of the Ruins for the rest of the game. After flying under the radar for the entire game, Casey is finally called out by her aggravated team.

A night of drunken partying turns violent when two players from opposing teams get into a fistfight. Susie finds herself at odds with her male teammates. Old tensions between Dunbar and KellyAnne are reignited and threaten the foundation of the Challengers' team.

Dunbar struggles with being the last remaining man on the Challenger team and must fight for survival in the game. Johnny contemplates drastic measures to get rid of one of his own teammates. Players battle in the last Ruins to secure a spot in the finale.

The Champions become paranoid that they could lose in the end if one worrisome team member fails to pull their weight.

The reunion was hosted by Maria Menounos and was taped at the MTV Studios. Cast members that attended were Landon, Evan, Rachel, Brittini, Aneesa, Kim, Dunbar, Brad, Tori, Diem, Mark, Jenn & Paula. The many relationships/hookups, fights & missions were discussed.