Based on Lindy Woodhead’s biography Shopping, Seduction & Mr. Selfridge, the series blends fictional characters and storylines with those inspired by the real-life people and celebrities from Selfridge’s life. Cosmetics queen Elizabeth Arden, blues singer Alberta Hunter, and vaudeville stars The Dolly Sisters are just a few of the famous faces that pop up in Season 4. To christen the final season, here’s a guide to some of the notable figures who have added sparkle, excitement, and drama to past seasons.