Eternal, A1, 3T, Girl Thing, Damage and newly-formed boy band 5th Story were pictured during their night on the razz and the snap shows how quickly they've bonded with each other.
Damage's Jade Jones, who is engaged to Emma Bunton, is laughing hysterically in the photo, while Girl Thing star Jodi Albert is also beaming.
Not all the stars could make it, however we can definitely spot a fair few familiar faces among the crowd!
Meanwhile, Damage spent time away from the other groups getting to know 3T - made up of Michael Jackson's nephews Taj, TJ and Taryll Jackson.
Sharing a picture of the two boy bands sitting together, Damage's Andrez Harriott said: "With the 3T team!"
The Big Reunion is due to return to ITV2 next month.
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