'Big Brother' Season 27 Mastermind Drops Compelling Clues About the "Accomplice"

Let's face it, Big Brother has been on the air for a really, really long time. If you had told the world back in 2000 that this wild idea of tossing a bunch of strangers into a house, locking them in, and watching them compete to be the biggest betrayer or the most popular housemate, you probably would have gotten some rightfully skeptical responses.

And yet, here it is, 25 years later.

Season 27 hit televisions in the Summer of 2025, and with it came some intrigue. CBS promised to make Season 27 full of twists and turns, and they delivered almost right away, by declaring that there was an "Accomplice" among cast members who was working against the housemates. Clues dropped here and there sparked a frenzy of speculation, but what do we really know about this shadowy figure?

Here's what we know so far.

In some ways, Big Brother is the literal big brother of all the reality television that has come after. Without the initial few seasons of Big Brother proving that the world was ready and willing to watch people locked in a house together, we wouldn't have the endless amounts of "lock them up together" reality television like we do today, including shows like Love Island, The Bachelor, and more. While you could argue that Road Rules and Real World are the parents of reality TV, Big Brother is the big brother, for sure.

This is why CBS was so determined to make 25 years of Big Brother something special, promising intrigue and interest.

Shortly after Season 27 kicked off, host Julie Chen Moonves disappeared, replaced by a mysterious figure known as The Mastermind.

Clues were dropped here and there as both housemates and fans speculated furiously, and a mysterious 17th houseguest arrived. A familiar face: Rachel Reilly, who won Season 13 of Big Brother.

But that wasn't all. The Mastermind declared that there was an "Accomplice" hidden among the housemates, and they were working behind the scenes with a hidden agenda. The big job? Figure out their identity.

After Rachel was revealed, clues about who the Accomplice might be consumed the fandom and the houseguests alike as they raced to be the first to determine who it might be.

And fans have been quick to supply their theories based on the clues provided.

On TikTok, @tommyitaliano_ provided a comprehensive look at the clues that have been sussed out and what people think they might mean.

The TikToker explains that one of the first clues people have focused on was that when the lights came back on after the sudden blackout, Keanu is spotted walking over to the living room. But as another fan notes, Eva was also spotted near Keanu.

Some fans have pointed out that it has to be a girl based on the guy/girl ratio in the house. If someone unmasked the Accomplice and they were eliminated and it was a guy, the ratio would be too far off.

@tommyitaliano_ believes that Katherine could have been the only person to push a secret button, but not everyone agrees.

In the comments, one user points out that when the lights went out, Amy appeared to hold a remote, adding, "She also kept lingering around the painting/door that Rachel came out of, which is 2/3 tasks the mastermind!"

And yet another fan speculated that it was Will, fiddling with something near the timer.

Who is the Accomplice? While there are ample clues, there's no solid answer yet. If CBS was looking for some drama to get people tuned in even after a quarter of a century, they seem to have struck Mastermind gold.