This borrows from the Greek myth of a box that contained all the evils in the world disguised as something good. If opened, the evils would be unleashed upon the world but possibly bring something good with them as well. This holds true in Big Brother, for when the Box is opened, it unleashes something good for the Head of Household and something bad for the house, or something good for the house and something bad for the Head of Household.
Pandora's Box has since been retired from the show, having not appeared from Big Brother 15 onward.
Pandora's Box has been the subject of controversy by fans of the show online, who accuse it of being a way for the producers to rig the game. Examples include the fact that the box sometimes seems to appear when a player favored by production is at risk of going home, and it contains a twist that either gives them immunity of puts them at an advantage for the week. Further, the fact that nobody has ever turned down opening the box has led to some speculation that the houseguests aren't allowed to do so. Porsche Briggs confirmed on the live feeds that she was forced to open her box; former houseguest Matt Hoffman has jokingly referred to the box as "Producer's Box", due to its high potential for unfairly rigging the game.
|Season||For the HOH||For the House||Opened By|
|11||Locked in the Box with a TV to watch the houseguests.||Money fell from the sky for them to collect. Kevin would not be released until the houseguests let him out.|
|Spent time with her boyfriend, who proposed to her. She had to forfeit her spot in the POV competition.||The House was tormented by costumed guests.|
|12||Granted the Diamond Power of Veto to be used at either of the next two evictions. He used the veto on himself when he and Lane Elenburg were on the block, and Kathy Hillis was the replacement nominee.||Unleashed The Saboteur 2.0 into the house.|
|Granted a spa retrieve, complete with a massage, access to the pool and other facilities, and a relaxing day in paradise.||Unleashed Juror Rachel Reilly into the House for 24 hours.|
|Locked in the Box with previous BB10 and BB11 houseguest Jessie Godderz, who forced her to work out, all the while boasting about himself, under the pretense of getting game advice.||Enjoyed a Hawaiian luau.|
|Had to choose envelopes from a tree. Each envelope had a different amount inside, with a maximum amount of $10,000. Lane chose three envelopes totaling $91.17.|| The house received a punishment for every envelope Lane opened.|
#1 Cutlery and cups were taken away.
#2 Wearing Sock Puppets and making them speak when the wearer speaks or risk becoming a Have Not
#3 Dancing to music every hour or risk becoming a Have Not
|13||Earned $5,000 along with chosen HouseGuest and now partner duo, Kalia.||The game returned back to the duos twist for one week with Porsche and Kalia, Rachel and Jordan, and Adam and Shelly becoming duo partners.|
|Locked in the Box with previous BB10 and BB11 houseguest Jessie Godderz, who acted as a salesperson who gave her anything that dealt with himself.||Tori Spelling entered the house and gave all the houseguests a three-minute shopping spree.|
|14||Had to choose three small cubes. Each cube had a different amount of money inside, with a maximum amount of $10,000. Frank won a total of $3,341.49. However, he was also locked in the Box for an hour.||Unleashed quarters throughout the Big Brother House to operate the crane game, which contained a Golden Ball of Veto. Ian Terry received the ball and had to forfeit playing in that week's Veto competition as he had just won a Veto.|
|Released small presents throughout the house (including a new hammock in the backyard)||Released BB10/BB11 houseguest Jessie Godderz into the house where he replaced all the junk food with healthy food.|
|Watched a video made by BB12 and BB13 House Guest Rachel Reilly, in which she gave him useless "advice" on how to win the game.||Received video messages from home.|
- Ian Terry is the only HouseGuest to open Pandora's Box twice.
- No houseguest who was offered Pandora's Box ever passed on opening it.
- Big Brother 13 was the only season to not have a male open Pandora's Box, while Big Brother 14 was the only season to not have a female open it.
- Big Brother 15 is the first season to not feature Pandora's Box since the twist started.
- Since the retirement of the Pandora's Box twist, the room it previously occupied has served a number of purposes. It acted as the Coach's HoH bedroom for the first 4 weeks of Big Brother 14, the second HoH's bedroom in Big Brother 16 and Big Brother 17, the secret Paris room in Big Brother 18, the Den of Temptation in Big Brother 19, the gym in Celebrity Big Brother, the BB App Store in Big Brother 20, and the Camp Comeback room in Big Brother 21 (US).