Watch first 3 minutes of Big Brother 25 premiere — and find out about a giant twist

Big Brother always says to expect the unexpected; in this case, that's dropping the first three minutes of the season 25 premiere a few hours early.

EW can exclusively share the cold open of tonight's episode, which will air this evening on CBS at 8 p.m. ET. The release of the footage comes on the heels of Big Brother confirming a long-rumored twist: "The #BB25 multiverse will release a mystery 17^th [houseguest]," reads a tweet from the official Big Brother Twitter (er, X?) account. "What's your guess for who it is?"

While our brains are reeling to figure out who that mystery houseguest might be, lets turn our attention back to the exclusive sneak peek: The billowing voice of Big Brother begins the opening in his traditional manner, welcoming viewers to "a house like no other" and running through the logistics of the production, including 94 cameras and 113 microphones used to capture all the action. But this being a milestone anniversary for the reality competition series, the intro then pivots to a lightning-speed retrospective of the past 24 seasons showcasing the 304 competitors who have entered the house over the years.

There's, of course, the one-liners like Rachel Reilly Villegas' "Floaters grab a life vest" and Britney Haynes' "I lost my dignity slippery wiener" (though sadly no replay of her Diary Room faces while tethered to Brendon Villegas), as well as a montage of all the iconic showmances, including Bayleigh Dayton and Chris 'Swaggy C' Williams (now married with a child), Jordan Lloyd and Jeff Schroder (now married with two kids), and the Villegases (also married with two kids). The Bachelor and Bachelorette franchises only have nine successful marriages total... just sayin'.

But as much as we love love, we love war even more — and Big Brother gifts us quick hits of some of the most memorable fights from the show's past. There's "Evel" Dick Donato banging the cooking pot lid, Janelle Pierzina saying "bye bye, bitches" to the Friendship (ugh, that name), and Ragan Fox's battle with Reilly Villegas (man, she really did tick off every box for great reality show TV).

After a celebratory lap for all the notable winners of seasons past, Big Brother finally turns its attention to the previously announced 16 new houseguests (including two with a Survivor connection) competing for $750,000. The voice of Brother teases this will be the most "unpredictable" season yet — and that's saying a lot for a show that's wilder than Passions was, with twins swapping places and half-siblings discovering each other in the house.

The 90-minute Big Brother 25 premiere debuts Wednesday at 8 p.m. ET/PT.

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