Here is a comprehensive summary of the Wikipedia article on Big Brother 28:

Big Brother 28, also known as Big Brother: Time Trip, premiered on CBS on July 9, 2026, and is set to conclude on October 1, 2026, introducing a time travel theme to the classic reality competition. The show maintains its core format where HouseGuests compete for the Head of Household title, endure nominations, and play for the Power of Veto, but a new "BB Block Buster" competition now reduces the initial three nominees down to two before the house vote on eviction night. A key new twist is the "BB Time Capsule", in which a weekly viewer vote sends one HouseGuest to attempt a challenge for a hidden power or punishment borrowed from previous seasons. The initial cast of 14 contestants, revealed on July 7, 2026, features notable reality stars like drag queen Jason De Puy (from RuPaul's Drag Race), Drew Campbell (Beast Games), Lyric Medeiros (American Idol), and Yash Patel (The Quiz with Balls). As usual, the last seven evicted HouseGuests form the jury to vote for the winner, while the public awards a separate $50,000 prize for "America's Favorite HouseGuest".