'Big Brother 15' Premiere Recap: New Twists Revealed as McCrae Becomes First Head of Household [VIDEO]

Big Brother 15 premiered Wednesday night with 16 new contestants and two game-changing new twists.

"Welcome to the biggest Big Brother ever!" said host Julie Chen to a cheering crowd outside the house. After a clip package introducing the 16 new contestants, Chen allowed them to enter the house four at a time.

After settling in, the group introduced themselves to each other. Many of the houseguests discussed the attractiveness of their housemates, indicating that there may be a few "showmances" blossoming this summer, including Aaryn and David, Amanda and Nick and Kaitlyn and Jeremy.

Two separate, secret alliances were soon made, both involving Jeremy. The first included Jeremy, Howard and Spencer who agreed to stick together in secret because of their strength. The other alliance included Jeremy, David and Jessie, who agreed to stick together for similar reasons.

The houseguests were soon blindsided when Chen told them that there would be three nominations every week instead of two, a first for the show. She said that the Head of Household would still nominate two houseguests but the process of nominating the third person would be revealed later.

The HOH competition involved the houseguests hanging on to swinging poles. During the challenge, Judd and Candice discussed Elissa and came to the correct conclusion that she was the sister of Rachel Reilly, the winner of Big Brother 13.

With only Jeremy, David, Nick and McCrae left in the competition, Chen offered them the option of not having to eat slop, a Big Brother tradition, for the rest of the summer. The person who dropped first would have to choose between two boxes, one of which had the pass and the other did not. After Jeremy persuaded him, David dropped down and picked the box with nothing in it. Jeremy dropped soon after and "won" the pass.

McCrae won the first Head of Household after Nick made a deal with him assuring his safety.

After the competition, Chen informed them of how the third nominee would be chosen for eviction. She told them that the Big Brother MVP twist would involve America choosing one player they felt was playing the best game who would then nominate another person for eviction in secret. The third nominee would be revealed before the Veto competition.

On Sunday night's episode, McCrae will nominate two of his fellow houseguests for eviction. It will air at 8 p.m. on CBS.

Click here to watch the full episode.