'Big Brother 18': Corey finally realizes he's playing a game

On Thursday's episode of Big Brother, James and Natalie's showmance was split when Natalie was unanimously voted out of the house. 

Sunday night's installment kicks off where we last left the houseguests: the head of household competition. To recap the rules:

The contestants each have a big vat of melted butter that they need to transfer across a slippery, buttery track. They have to carry the butter using small scoop to fill up a big bowl on the other side of the track. They can choose to fill the big container first or they can fill a smaller bowl first. If they fill the small bowl, they get access to a bigger scoop that they can use to fill the big container more quickly. 

Although Paul and Victor seem to want to stay loyal to their final four deal with Nicole and Corey, Nicole reveals in the diary room that she and Corey decided before Thursday's eviction that it might be a good idea to get Paul or Victor out because they are both "very threatening." 

In a flashback to 45 hours before eviction, Nicole tells Corey she wants to make big strategic moves. In order to increase their odds of being safe the following week, Corey tries to pull James on their side. 

Corey ends up winning the butter-filled competition. "Now I need to choose who's going to final four with me and who's best for my game," he says in the diary room. 

All of the contestants are happy with Corey's win. Paul and Victor believe that Corey will stay loyal to their final four deal and evict James, while James thinks he might be safe since he's on good terms with Corey and Nicole. 

"I'm feeling pretty confident," Paul says in the dairy room. "I'm feeling pretty safe. That's another win for the final four ... No matter what happens this week, your boy is safe."

In another flashback, this time to 40 hours before eviction, James wants to make sure he and Natalie are still on good terms despite all the awkward tension since being nominated for eviction. 

"I just want you to know I still care about you," James says. 

"I would never use you," Natalie says to him. 

After Corey receives his HOH room, Nicole asks him what they're going to do this week and says she's scared. "Odds of going to final three are better with James in this house," he tells her. "I want Vic then Paul." 

"I'm going to crap myself when their faces pop up," Nicole says of the nomination ceremony.

Nomination ceremony

Prior to the ceremony, Paul asks Victor if he thinks Nicole and Corey would ever "fuck them over." 

"Not if they are true to their word," Victor responds. 

When Paul asks Nicole and Corey what the plan is, Paul explains he doesn't care whether they put him or Victor up next to James. "If all goes well this should be a pretty smooth week," Paul says in the diary room. 

Corey ends up nominating his former alliance members, Victor and Paul. "Strategically, it's not in my best interest to put James up ... I gotta make a big move," he says to the houseguests. 

Find out who wins the power of veto competition on a special eviction episode of Big Brother, which airs at 8 p.m. Tuesday on CBS.