'Big Brother' 21: Who's on the Block After First Nomination Ceremony?

It's still only week one in the Big Brother house, but things are already gearing up for a potentially powerful alliance of eight spearheaded by Head of Household Christie Murphy. During Sunday's episode of the CBS reality show, "Gr8ful" debuted as a force to be reckoned with going into the house's first nomination ceremony, with the HoH putting up Cliff Hogg III and Kathryn Dunn for potential elimination.

Christie, working with Jackson Michie, Jack Matthews, Isabella Wang, Nick Maccarone, Holly Allen, Tommy Bracco and Analyse Talavera, aimed to get out of the first HoH stint with her hands clean, and was rubbed the wrong way by Kathryn's "paranoid, weird kind of energy."

"My main priority this week is to get out of this HoH with no blood on my hands, and the way that Kathryn is running her mouth, it seems like no one would miss her," Christie said in the diary room. "So I think I've found my first nominee. Like always, the universe delivers things when I need it to."

Cliff accepted his role as a pawn when asked by Christie if he would be willing to go up on the block beside Kathryn, but admitted to the camera later that as the season's oldest player, he was worried he would be going home anyways.

As the alliance of eight attempted to keep their majority a secret, things got thrown for another loop with the Whacktivity Comp twist, which will pit five houseguests against one another each week in either a Chaos, Panic or Nightmare activity, all for a secret bonus power in the house. Ovi Kabir managed to take home the victory at the end of the day, keeping his bonus power to force a surprise, middle-of-the-night second nomination ceremony close to the vest in hopes of protecting himself with a new alliance — that was unfortunately all members of the other alliance placating him.

As the nominations drew clearer, Kemi Faknule also found herself in the potential line of fire, as her straightforward talk about game threatened some of the other players who thought she would be ready to throw them under the bus without warning.

With the Power of Veto still up for grabs, and with Ovi's power still in play, who will actually find themselves going home this week?

Big Brother next airs Tuesday, July 2 at 8 p.m. ET on CBS.

Photo credit: CBS/Sonja Flemming