Marcos Timoleon (a career-defining role for Willem Dafoe)—a Greek billionaire modeled after Aristotle Onassis—hosts a lavish 25th birthday party for his daughter (Vic Carmen Sonne: *The Girl with the Needle*) on his private island, inviting the global elite and the band The Animals. He intends to announce her engagement to the son of a wealthy business associate. However, she is in love with someone else: the struggling ghostwriter (Joe Cole: *Peaky Blinders*) currently penning her father’s biography. An authoritarian figure who brooks no dissent, Marcos will stop at nothing—resorting to intrigue, blackmail, and worse—to execute his succession plan, for family is the toughest business of all.