Julie Chen returns to host the eighteenth season of Big Brother.

Big Brother - Season 18 Episode 1 Season Premiere (2)

New twists are revealed.

A new weekly competition is revealed.

The Power of Veto competition is held.

A house guest is evicted; the head of household competition and the Battle Back competition begins.

The first five evicted house guests compete in "Battle Back" competitions; the last evictee standing will return to the game for another chance at the $500,000 prize.

The battle for the final HoH begins. Plus the Final Three celebrate the Summer.

Who will become the final HoH and who will make it to the final 2? Thirteen houseguests have departed and tonight, nine will have to make a difficult decision. Who will be crowned winner of Big Brother and walk away with the half million dollar prize, and who did America vote as their favorite houseguest?