Article continues below advertisementThe Pussycat Dolls are officially staging a comeback - and this time, they're doing it as a trio. Original members Nicole Scherzinger, Kimberly Wyatt and Ashley Roberts have reunited, releasing a new single and announcing a global tour marking the 20th anniversary of their breakthrough album PCD.The revival arrives amid a broader wave of nostalgia-driven reunions across pop music, a trend that experts say continues to resonate strongly with fans who grew up during the early 2000s pop era.