Big Brother season 27 episode 5 premiered on CBS on July 20, 2025. It marked the start of the second week of the competition with contestants competing for the second Head of Household tenure of the season.This week's HOH competition broke from the usual format as Mastermind secretly stepped in to introduce a major twist.Before the competition, the contestant received a message through a police bulletin informing them that the Mastermind had broken into the house and stolen the HOH key, as well as three mystery powers. The contestant had to participate and compete to either secure the HOH key or go for one of the mystery powers.When the powers were revealed, they centered on gaining additional opportunities related to the Head of Household and Power of Veto.Who won the three Mastermind's powers in Big Brother season 27 episode 5? View this post on Instagram Instagram PostIn Big Brother season 27 episode 5, the houseguests were informed through Red light alarms and a police bulletin that the Mastermind had broken into the house and stolen the HOH key and three mystery powers. He was chased by BB's police department into a hotel, where he stashed all the loot he had taken from the BB house.The house guests were told that the items stolen by the Mastermind were still in the hotel's sewers. To retrieve and claim them, they would have to navigate through a dark, sewer-like structure, relying on their instincts in near-total darkness.The darkness aspect felt too much for some contestants, including Ava, who chose to sit down at the spot for the entirety of the challenge. In contrast, others rushed to secure the HOH key to add another week to the journey, while some felt the mystery powers would be more beneficial for them.In the end, Jimmy secured the HOH key while Kelley, Keanu, and Mickey found the individual mystery powers. While everyone eventually got to know that Jimmy had won Big Brother's second HOH, only the holders of the mystery powers knew about their win and what their power was about.Kelley's power granted her a chance to play in secondary Power Of Veto competition after the first POV takes place and the winner decides on the name of the contestant whom they want to save from the chopping block.If Kelley manages to win the secondary POV, she will have the opportunity to put another name in to save from the risk of being eliminated. View this post on Instagram Instagram PostThis means that whoever is the HOH during that particular Big Brother season 27 week could be put in a situation where they would have to name two replacement houseguests for nomination if both the POV winner chooses to use their power.Keanu's power granted him the chance to bring in a mystery houseguest to take his place during a particular POV competition. This mystery houseguest would be a former Big Brother contestant, and if they manage to win the competition, they would give the POV to Keanu to use during that week.While the first two mystery powers revolved around the POV competition in some fashion, Mickey's power allowed her to snatch away someone's HOH powers during a particular week.The power, though, came with a time limit, and the Big Brother contestant had to use it before the jury week set in motion.Whenever Mickey decides to use her power, the current houseguests will be allowed to interrogate one another to uncover who activated it. If the HOH correctly identifies Mickey as the one behind it, she loses the chance to take over. However, if they fail to identify her, Mickey will officially take over as HOH and receive all the powers that come with the position.Big Brother season 27 premieres every Wednesday, Thursday, and Sunday on CBS.