The actress, 81, will guest-star on the network's first scripted series as the Grand Duchess of Oxford, the mother of Queen Helena (Elizabeth Hurley). She's "the only woman in the world more formidable and imposing" than Helena and when she arrives, she'll bring "an entourage and an agenda," according to the network.
"I am delighted to be part of this very entertaining project," Collins said.
In addition to Dynasty, Collins has appeared on Rules of Engagement, Footballers' Wives and Will & Grace.
The Royals is set to premiere on E! in early 2015.
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