This marks a reunion for King and Plec.
MacKenzie also was a writer-producer onThe Originals.
It centers on the wealthy, seemingly perfect Sinclair family, who spend every summer on their private island.
Mamie Gummer, Caitlin FitzGerald, and Candice KingBrigitte Lacombe/Getty/Catherine Powell
Gummer, FitzGerald and King play the three Sinclair sisters.
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Gummer is Carrie Sinclair, the eldest daughter of a wealthy media mogul.
She was once the most rebellious of her sisters, but her wild days are seemingly over.
King plays Bess Sinclair, the youngest Sinclair sister.
At least, they seem happy, posing together in the Boston society pages.
Also executive producing are Emily Cummins for My So-Called Company and the novels author, Lockhart.
Universal Television, a division of Universal Studio Group, and Amazon MGM Studios are the studios.
FitzGerald is currently filming the independent featureAbove The Below,opposite Idris Elba and Hero Fiennes Tiffin.
King is repped by Untitled Entertainment and Jackoway Austen Tyerman.
