Nikki, 28, who has become one of the show's most iconic housemates ever with her 'Who is she?' rant, will be entering a secret bunker in the house as part of a new twist.
Nikki and two other legendary housemates will be living in a secret room, and they'll be joined by either Simon Gross, Marc O'Neill and Sam Kay, who face eviction tonight, only little do they know that it's fake!
Nikki, who has been living in France for the past six months, headed to London this week, where she told fans: "Au Revoir Paris, you've given me the best 6 months I could have dreamed of! London awaits... Here's to the next chapter!"
And, taking to Twitter this afternoon, Nikki shared a photo of herself packing a suitcase. Captioning the snap, she said: "Packing packing packing!"
Confirming her return, Nikki told our friends over at Digital Spy that she's excited about returning with past housemates.
"I'm so excited," she said. "It depends who it is! I've watched every series so I'm aware of everyone. But I'm excited. I think I'll just deal with it at the time. Listen, I've been in with John McCririck and Coolio so if I can do that, anything can happen."
Nikki will be joined in the secret bunker by two other legendary housemates and the 'evicted' housemate. Earlier this week, it was rumoured that Nikki would be joined by Helen Wood and Gina Rio, but since, lots of other names have been thrown into the mix.
In what's being called 'Time Warp' week, the legendary housemates will only be living in secret for 48 hours before they'll be sent back into the main house where they will live for one week.
Tune into Big Brother tonight at 9pm on Channel 5.
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