"Big Brother" is back with the season 27 premiere Thursday. Here is everything to know about the episode and the new season.

Since its premiere on July 5, 2000, Big Brother has continuously evolved, tweaking its gameplay and format while delivering many twists and turns. This constant evolution aligns perfectly with host Julie Chen Moonves ' iconic reminder each season: "expect the unexpected."

"Big Brother" is celebrating its 25th year on air. A new season premieres Thursday with 16 new house guests competing and strategizing to evict one of their own each week until only one remains. "Entertainment Tonight" correspondent Denny Directo spoke with host Julie Chen Moonves about the season.

According to host Julie Chen Moonves, a fan-favorite twist will be returning for Big Brother 27 to challenge the houseguests once again.

Not even The Masked Singer fandom is that good at figuring out identities that quickly, so props to the Big Brother fans who figured all of this out with so little information in less than a day. CBS may want to uses masks next time.

Julie Chen Moonves is the host of CBS' long-running reality show, Big Brother, which premieres its 27th season this week. (CBS Broadcasting, Inc.)