The new season of the hit reality competition series "Big Brother" includes new elements including the introduction of a mysterious masked visitor with a secret accomplice and an unknown houseguest to be revealed sometime during the season.

The “Big Brother” 27 live feeds won’t begin until Sunday, July 13, at 12:30 a.m. ET, which is three full days after the premiere. It’s likely that the feeds are being delayed to preserve the mystery houseguest’s identity, which suggests that we won’t know who they are until the July 13 episode of “Big Brother.”

Julie Chen Moonves returns to host Big Brother Season 27, which premieres with a 90-minute episode on Thursday, July 10 at 8 p.m. ET on CBS. A second 90-minute episode will follow on Sunday, July 13 at 8 p.m. ET. RELATED: ‘Survivor 50’ Cast Photos: All The Castaways Confirmed For CBS Competition

CBS’s Big Brother returns with a new season packed with twists. Among the contestants: Amy Bingham, an insurance agent from Stockton. Here's how she plans to win.

I'm a Big Brother fan, and like Tucker from BB26, I also "really like puzzles!" Especially crossword puzzles. So naturally, it's my idea of a good time to put together a crossword puzzle that's solely focused on Big Brother (U.S. edition).

I never expected that person. And I was very excited because, in my opinion, getting that person is epic,” the host said.