For both Emma Corrin and Elizabeth Debicki, the road to “The Crown” began with failed auditions. Each performer was up for a guest part in the Netflix series’ early seasons; both ended up playing Princess Diana at different ages. Corrin was Emmy-nominated for portraying the newly wed and then increasingly disillusioned princess in Season 4. Debicki, previously a nominee for Season 5, which centered on Diana’s divorce from Prince Charles, is eligible for a nomination this year for the show’s final season, in which Diana tragically dies in Paris. Corrin has springboarded off their “Crown” success into further risky and intriguing roles — this season playing the enigmatic and dogged sleuth Darby Hart on FX’s snowbound mystery “A Murder at the End of the World,” created by Brit Marling and Zal Batmanglij.