“Big Brother” Season 21 will premiere on CBS on June 25. Just like in the previous seasons, the first episode from Season 21 will be a two-night event that will continue until June 26.

On June 25 and 26, “Big Brother” Season 21 will air at 8 p.m. But starting July 10, the reality TV show’s usual Tuesday and Wednesday schedule will be moved to a Wednesday, Thursday and Sunday schedule. Weekday episodes will air at 9 p.m., and the Sunday episode will air at 8 p.m.

Julie Chen will return as host of Season 21. The wife of former CBS CEO Les Moonves has been part of the “Big Brother” franchise since it premiered almost two decades ago.

Meanwhile, CBS entertainment president Kelly Kahl said that the fate of “Celebrity Big Brother” Season 3 is still uncertain as of late. The first two seasons of the spinoff averaged just over a 1.0 demo rating.

The upcoming season of “Big Brother” is expected to run for approximately 100 days, just like the previous installments. Sixteen relatively unknown houseguests will be secluded inside the “Big Brother” house with people they don’t know.

Throughout the entire seasons, twists, challenges, secrets and evictions will plague the household. But in the end, only one houseguest will be named as the winner and will bring home the $500,000 grand prize.

In the past, some of the contestants on “Big Brother” have moved on to do other things. For instance, “Big Brother” Season 19 winner Josh Martinez appeared on “The Bold And The Beautiful” as Chef Josh.

His fellow houseguests Jessica Graf and Cody Nickson, who have become a real-life couple, also competed on the “Amazing Race” and won. Graf and Nickson have already tied the knot, and they have been blessed with a daughter together. Graf also previously appeared on “The Bold And The Beautiful.”

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