Big Brother 1

 is the 21st season of the broadcast edition of Big Brother (U.S.).

Development
CBS announced that Big Brother had been renewed for a twenty-first and twenty-second season on May 15, 2019. CBS later announced on May 20, that the twenty-first season was set to premiere on June 25, 2019. Unnamed insiders close to the production of the show previously cast doubt if Julie Chen would return to host following sexual misconduct allegations against her husband Les Moonves. Chen Moonves however, returned for Celebrity Big Brother 2 (US) and it was later announced that Julie Chen Moonves would return to season 21.

Allison Grodner and Rich Meehan to return as executive producers for the series which is produced by Fly on the Wall Entertainment, in association with Endemol Shine North America.

Casting
Despite not having an official renewal announcement from CBS at the time, casting for the season was open until April 2019. Kassting, Inc. returned to provide casting services for a twentieth consecutive season since season 2 with Robyn Kass serving as the casting director.

It was then announced by former season 11 & season 13 contestant, Jeff Schroeder that the houseguests would officially be introduced on June 17 at 11 AM ET/8 AM PT on the live feeds, after they were released an hour earlier.

Cast Relationships
Moments after the cast was revealed, it was noticed by fans that many of the new houseguests have a relationship with one another. Christie Murphy used to date Tommy Bracco's aunt and is tagged in many of each other's Instagram photos. It was revealed by Rob Has a Podcast Life Feed Correspondent, Brent Wolgamott that Holly Allen and Kathryn Dunn were friends and knew that they would be cast together for weeks prior to sequester.

Air Schedule
The season features an initial time slot change from previous seasons; new episodes are set to air on a Sunday/Tuesday/Wednesday schedule through the first six episodes before returning to a traditional Sunday/Wednesday/Thursday schedule as in previous seasons.

The 24/7 internet live feeds are also expected to return with a CBS All Access subscription following the two-night season premiere on June 26. In addition, Big Brother: After Dark is expected to return on Pop also following the two-night premiere on June 26 or June 27, depending on viewers local time zones.

House Reveal
As with previous seasons, the program is filmed at CBS Studios, sound stage 18 in a custom-built two story house. The House is equipped with 94 high-definition cameras and over 113 microphones in order to monitor and record the houseguests. The living room, three bedrooms, kitchen, dining room, bathroom, and lounge room are located on the first floor. The Head of Household bedroom and bathroom, and an additional lounge area known as the "Sky Bridge" are located on the second floor. The second floor is accessible by a ladder located in the entry way or a spiral staircase located in the kitchen next to the sliding glass doors that lead to the backyard. The backyard area features outdoor amenities for the houseguests. Entertainment Tonight showed the first look at the house with Kevin Frazier during their episode on the night of June 20, 2019. Entertainment Tonight then released a sneak peek of the house through a brief tour on their website on June 21. Meanwhile, a full house tour with the host, Julie Chen, and other photos were released through the show's social media outlets.

The house theme matched the season's overall theme and received a camp theme; Production Designer Scott Storey designed the house's features. The living room features a birch-wood coffee table and a large and a 23-foot triangular window illuminated by LED lights. The first bedroom features a "sleeping under the stars" theme and includes two double-beds and the exterior of a camper. The camper, is only a facade into the second bedroom which features three double-beds and is assumed to be that of a camp counselor's bedroom. The third and final downstairs bedroom is a sports-themed bedroom primarily based from archery. In the kitchen many of the appliances have been redone in an attempted to blend them in with the rest of the theme, an electronic camp fire has been added to the center of formal dining table. The downstairs lounge area received a boat theme while the bathroom received a boat house like theme. The upstairs lounge area, for the first time in the series history is also accessible by a ladder from the entry way, has been updated to resemble a tree house; the Head of Household bedroom and bathroom have been changed to resemble a Moroccan-style bedroom. The backyard features a pool with kayak's and an attached hot tub, lawn chairs surround the back yard which also features a pool table and a washer and dryer, workout equipment, outdoor lounge areas, a hammock, and a mini-fridge.

Multiplatform Coverage
In the pattern of the past few seasons, this season will have coverage among multiple platforms.

Twists

 * Pre-Existing Relationships: Among the sixteen houseguests, there are various that had known each other each before entering the house. The show acknowledged that Christie Murphy was in a previous relationship with Tommy Bracco's aunt during the premiere. However, it was discovered online that Holly Allen and Kathryn Dunn had been friends for years, and are Facebook friends. The show did not acknowledge the relationship between Holly & Kathryn until Episode 14, the eviction episode for Week 4.
 * Camp Director: On Night One, the houseguests had to elect a "Camp Director" to rule over the house. The winner would have the power to banish four houseguests to the Hit The Road competition where the loser would be evicted from the house.
 * Hit The Road: The four banished houseguests from the Camp Director would be secluded to the backyard where they would have to battle to survive in order to stay in the house.
 * Whacktivity Competition: Every week for the first three weeks, five houseguests would competed in a camp-themed competition in order to win a secret power. The winner would be awarded in private and be given a secret power. Due to Camp Comeback, any player who wins a Whacktivity Power and then gets evicted is allowed to regain the power if they return to the game.
 * Nightmare Power: After the Head of Household makes their nominations, the winner would be able to activate the power to nullify the nominations and wake everyone up in the middle of the night and force the Head of Household to name two new nominees on the spot. This power lasts for the first six nomination ceremonies.
 * Chaos Power: After the players have been drawn for the Power of Veto competition, if the winner is not satisfied with the player selection, they would be able to force the HoH and the two nominees to redraw the players. This power lasts until the Final Six.
 * Panic Power: Before the PoV Meeting, the winner may anonymously grant that week's PoV winner the Diamond Power of Veto. They have the following four Veto Meetings to activate the power.
 * Diamond Power of Veto: If granted the DPoV by the Panic Power winner, the Veto Holder has the ability to name the replacement nominee if they choose to save an initial nominee, taking that power away from the HoH.
 * Camp Comeback/Previously Evicted Contestant: Starting after the second eviction, the evicted houseguest, along with the returning banished houseguest from the Hit The Road competition, would continue to live in the house. The evictees would be able to participate in the social game. They will not be able to participate in competitions and ceremonies, they will be secluded to the Camp Comeback Cabin. The twist will end after the fourth eviction. The first four evictees would battle in a Comeback Competition, where the winner returns to the main game, while the other three go home for good.
 * No Have-Nots: Due to the Camp Comeback twist causing the evicted houseguests to sleep in a room with Have-Not style living conditions, there were no formal Have-Nots for the first three weeks, meaning they were still allowed to eat real food and take warm showers. Once the Comeback twist ended in Week 4, Have-Nots came into play and the Camp Comeback Cabin became the Have-Not Room for the rest of the season.
 * America's Field Trip: During Week 6, America will vote to send three houseguests on a "Field Trip". The rules are very similar to the Temptation Competition from Big Brother 19 (US). The three houseguests who receive the most votes will face off in a competition in Week 7, where the winner gets immunity, the runner-up gets a punishment, and the loser becomes the 3rd nominee.
 * America's Prankster: As an addition to Prank Week, America will vote to give one houseguest the power of "America's Prankster", granting them the ability to secretly control one nominee during the week. The Prankster will overtake one of the HoH's nominations in a combination of the Co-HoH and Hacker Competition twists from Big Brother 18 (US) and Big Brother 20 (US). If the PoV is used on the Prankster Nominee, the Prankster will secretly name the replacement.

Prank Week
Prank Week took place from the end of Week 8 throughout all of Week 9, the houseguests will face a series of pranks played on them by both production and America.


 * BB Birdwatching Audio Tour: On Night 64, before the eviction of Week 8, the houseguests were told to listen to the announcements playing different bird sounds and what names are associated to the sounds, as a form of studying for the upcoming HOH quiz competition. However, on Day 65, Julie revealed that none of those sounds had anything to do with the HOH competition, as the start of Prank Week. The real competition was "Prank Shot", a skill competition.
 * Pie Punishment: The two houseguests who scored the lowest amount of points in the HoH competition would be given a punishment where they would have to make pies and either pie themselves, each other, or another houseguest at any time they are signaled to do so, including in the middle of the night. Because two houseguests tied for the second-lowest score, both were punished, upping the punishment to three people.
 * Opening Sequence: The intro narration and segue into the opening credits was filled with pranks and clips from the previous season.
 * Slimy Veto Draw: When the HoH and the two nominees place their hands into the box to select a chip during the Veto Draw, they will be sticking their hands into a vat of slime.
 * Zingbot Competition: Big Brother's resident prankster, The Zingbot, will make his annual reappearance during Prank Week.
 * Clown Sightings: Big Brother would constantly display projections of scary killer clowns throughout the one way mirrors within the house.

Trivia



 * With their 21st season, the Big Brother U.S. English speaking edition will be the first country to air 21 civilian seasons of the show.
 * This is the first season since Big Brother 17 in which the eventual winner did not win by a 5-4 vote.
 * Jackson Michie won by a 6-3 vote.
 * This season is tied with Big Brother 14 and Big Brother 22 for the most amount of consecutive HoHs to also win the PoV with three.
 * This was accomplished by Jessica, Tommy, and Jackson during weeks 6, 7, and 8 respectively.
 * This season has the shortest Have-Not Phase, with it only lasting for two weeks.
 * The opening sequence included the theme music last used from Big Brother 11 (US) to Big Brother 13 (US).
 * Ironically, the first and last evictee both returned for Big Brother 22.