Frank and Paulie are (once again) running the Big Brother 18 house, but from opposite sides. With Frank gunning for Da'Vonne and Paulie going after Tiffany, Thursday's eviction could be very revealing about where the other houseguests' loyalties truly lie.

So who won the fifth week in the Big Brother house? Check out our power rankings below. (For previous rankings: Week 1, Week 2, Week 3, Week 4.)

Category 4 (team average: 5.2)

Frank: Love him or hate him, you've got to respect Frank. After being blindsided at the last eviction, Frank didn't miss a beat, nearly winning HOH and amassing quite the ragtag team of allies. Now that he has Bridgette under his thumb, Frank practically got Tiffany to promise her firstborn to him in exchange for safety. And since Tiff won Road Kill, that means that Frank once again had a hand in the nominations and won the week.
Grade: 7 (Season average: 7.3 )

Paulie: Paulie is so laser-focused on Tiffany being Vanessa's sister that he's become blind to the facts -- that Tiffany isn't great at comps or the social game, so she doesn't pose much of a long-term threat -- and wasting his HOH. Paulie needs to learn to adapt his strategy more if he wants any chance at getting himself (and his showmance squad) to the end.
Grade: 6.1 (Season average: 7.1)

Michelle: Unsurprisingly, Michelle didn't do much this week. However, she did reveal herself to be quite the mean girl when she got mad at James for talking to Tiffany. Not talking game. Not even talking sh-- about other people. Simply talking to her out of kindness since she has no friends in the house and is possibly going home. Way harsh, Tai.
Grade: 4.5 (Season average: 4.8 )

Bridgette: Bronte seems to be the glue that held the Spy Girls together, because with her gone, Bridgette and Natalie don't appear nearly as close. This also could be due to the fact that Bridgette has dedicated herself completely to Frank and his game, which isn't helping her popularity with the other houseguests, who threw a bigger birthday party for a stuffed giraffe than they did for Bridgette.
Grade: 3 (Season average: 3.4)

Freakazoids (team average: 6)

Tiffany: With no friends in the house, Tiffany decided to align herself with Frank and Bridgette. But even gaining that bit of security didn't stop her from having a complete meltdown shortly after (which she later claimed was 80 percent strategic). However, knowing she was a major target this week, Tiffany won the Road Kill comp and made the great choice to put Day up as the third nominee replacement, exponentially increasing her chances of staying.
Grade: 6.7 (Season average: 5.8)

Corey: Corey hasn't done much all season other than be an extra vote to support whatever Paulie and Nicole want. But when his life was on the line, Corey managed to take himself off the block after winning a mental POV comp -- but don't let this fool you. Corey was still as thick-skulled as ever this week, declaring multiple times that he knows Tiffany didn't win the Road Kill comp.
Grade: 5.9 (Season average: 5.7)

Nicole: Despite previous declarations to the contrary, Nicole is getting extremely wrapped up in her relationship with Corey. We just hope Corey gets the boot soon so Nicole can get back to focusing solely on her gameplay.
Grade: 5.3 (Season average: 6.6)

Team Unicorn (team average: 5.5)

Natalie: Natalie is such a Victoria, but since Victoria made it to the Final 3, we probably shouldn't count Nat out just yet. And her relationship with James and growing friendships with the other girls in the house can only help Natalie's standing going forward.
Grade: 5.5 (Season average: 5.8)

James: James showed his cards this week, when he revealed he'd rather vote out Corey than Natalie, much to Michelle's chagrin. James also found himself being gently recruited by Frank's side of the house, so there's room for him to potentially switch sides if he thinks Paulie's crew might go after him or Natalie.
Grade: 5.5 (Season average: 6.3)

Big Sister (team average: 4.4)

Paul: Paul made himself useful this week by becoming Paulie's spy, infiltrating Tiffany and Frank's alliance and feeding information back to Paulie. Over the past few weeks, Paul's been so successful at shedding the stigma associated with his alliance with Jozea and Victor, we wonder what how his game will (or won't) change if either of those evicted houseguests returns this week in the Battle Back.
Grade:6.2 (Season average: 5.5)

Zakiyah: Zakiyah once again simply existed this week. And if the showmances really are targeted soon, Zakiyah should be worried, since she's focusing far more on her relationship with Paulie than the game.
Grade: 4.9 (Season average: 5.4)

Da'Vonne: All of Day's previous gameplay came back to bite her, with both sides of the house coming to see her as a target due to her constant meddling and manipulation. And Day only made things worse for herself when she went to James -- who's in a showmance -- about targeting the showmances. She later broke down crying after Corey won POV and began acting incredibly suspicious about Tiffany to Tiffany! There are no excuses for that type of idiocy, but we will miss her epic shade and hair-flips if Mama Day gets evicted.
Grade: 2 (Season average: 6.1)

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