Penelope Featherington

In 1813, Penelope debuts alongside her sisters, Prudence and Philippa, without anyone noticing. She spends afternoons with Eloise and daydreams about Colin Bridgerton, who only sees her as a friend. Her mother, Portia, is fixated on marrying off her daughters and barely notices the youngest. When her cousin Marina Thompson arrives at the Featherington house, pregnant and hiding it, Colin falls for Marina and nearly proposes. Penelope suffers in silence until the truth about Marina goes public and the engagement never happens. By the end of the season, the family also loses its father, Lord Featherington.

In the season's final scene, the show tells viewers what all of London wants to know: Penelope is Lady Whistledown, the anonymous author of the gossip sheet that drives high society. She's the one who exposed Marina's pregnancy. No one in the story suspects a thing. For viewers, the whole season suddenly reads differently: every scene of Penelope listening in from a corner of the ballroom becomes a clue, and Julie Andrews's voice finally has a face.

The next season, the queen is hunting Lady Whistledown, and Eloise decides to find out who she is too. Penelope relies on modiste Genevieve Delacroix to deliver her columns unseen. Trying to shield Eloise from one scandal, she causes another. In the end, Eloise finds out the truth and ends their friendship. Penelope considers stopping, but then overhears Colin tell his friends he would never court Penelope Featherington. Hurt, she decides to keep writing.

Tired of waiting, and still estranged from Eloise, Penelope swaps the yellow gowns for a new look and sets out to find a husband. Colin, back from his travels and full of regret, offers to help her gain confidence. Lord Debling takes an interest in her, but Colin realizes what he feels and declares himself. They get engaged.

The secret can't hold, though. Cressida Cowper claims to be Lady Whistledown, and Colin figures out the truth on his own and feels betrayed. At the final ball, Penelope steps forward and confesses in front of everyone. The queen chooses to forgive her, and the couple makes up. In a flash-forward, they're parents and authors, and Penelope publishes under her own name.

In Julia Quinn's books, Penelope is the heroine of Romancing Mister Bridgerton (2002), the fourth novel, which the show adapted in S3. In the books she has a fourth sister, Felicity, who isn't on the show. Nicola Coughlan plays her.