The Good Liar focuses on Roy Courtnay (Ian McKellen), a veteran conman and born liar who meets wealthy widow Betty Macleish (Helen Mirren) online and believes she’s an easy mark. Roy is sure he can pull off the final coup of his career, but as the narrative entwines Roy’s and Betty’s futures, it also delves deeply into their pasts, revealing nearly a century of secrets. Before Roy can close the deal, there is a reckoning to be made.