The cast of the upcoming season of Big Brother includes an ex-girlfriend to a The Bachelorette contestant, among other surprising houseguests. There will be 16 new houseguests from all over the country who will live (and compete) in the Big Brother house for its 21st season.

Big Brother has been bringing 16 strangers together as housemates for 19 years, where the show records their every move through constant surveillance. The Big Brother house is outfitted with microphones and HD cameras monitoring them 24 hours a day, and this tried and true format for reality TV was introduced in season 1 of Big Brother, which aired in 2000. The premise is simple: contestants must make alliances and avoid getting voted out each week at eliminations to make it to the grand prize of $500,000.

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For the 21st season of Big Brother, the show is introducing a very diverse array of cast members, according to Us Magazine, which includes a Broadway dancer, a petroleum engineer, a college student, a therapist, a truck driver, a preschool aid, a model, and a fitness trainer. The diverse cast brings each their own unique perspectives, skill sets, and personalities. However, the contestant that seems to be grabbing the most attention is The Bachelorette's star Luke Pell's ex-girlfriend Holly Allen. The Bachelorette alum who appeared on Bachelor: Winter Games said he ended his brief relationship with Stassi Yaramchuk on the show because he was still hung up on his on-again, off-again ex-girlfriend Holly. While the two reconciled and began dating after Luke left Bachelor: Winter Games, they ultimately broke up in May 2018.

Holly Allen Big Brother Season 21

According to her "Meet Holly Allen" Big Brother video on CBS All Access, Holly is currently a wine safari guide that works on a vineyard in Malibu that rescues exotic animals. Allen refers to herself as an honest person who is "too trusting," though "typically not very gullible," as her complicated dating history has made her slightly more hyperaware and cynical. Her goal for the show is to get through Big Brother with "minimal tears."

Holly explained that her past relationship with the former The Bachelorette star ended due to him being inauthentic. Hopefully, Allen will be able to use this ability to see through inauthentic people in order to build alliances within the game. She also admires past Big Brother contestant who played the genuine games. When asked by the host on CBS All Access whether she would rather win Big Brother and be hated or to lose the show and be loved, Allen chose "lose and be loved," because she said she'd rather walk away with her head held high, knowing that she played the most authentic game she could.

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The premiere of Big Brother Season 21 airs June 25 at 8pm EST on CBS.

Source: Us Magazine, CBS All Access