However, Bit On The Side host Rylan refused to reveal who the third legendary housemate will be!
Speaking on ITV's This Morning, Rylan said: "Helen is very controversial and she's promised to stir it up."
Meanwhile Nikki, who already confirmed her return earlier today, said in a new VT: "I cant wait to mix it up and stir some trouble." Rylan was pleased with Nikki's casting, saying: "She is going to be absolutely brilliant."
But when it came to who the third returning housemate would be, Rylan said: "There's been a couple other names, but you haven't guessed it."
So now, Nikki, Helen and one other famous housemate will return to the house tonight and live in a secret bunker for 48 hours. They will be joined by either Simon Gross, Marc O'Neill or Sam Kay, who are up for eviction, but are unaware that it's fake. One of those three will enter the secret lair with the legendary housemates.
After the 48 hours, all housemates will return to the main house, with the legendary housemates staying for one week.
Tune into Big Brother tonight at 9pm on Channel 5.
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