A chance accident brings Charlotte Heywood to Sanditon, a seaside resort on the cusp of dramatic change. Spirited and unconventional, Charlotte is initially keen to experience everything the town has to offer, but is then shocked by its scheming and ambitious inhabitants, and intrigued by the secrets they share.

Charlotte sets out to avoid Sidney, until a serious accident forces them together and to reappraise each other. When Tom brings a new doctor to the town, he and Lady Denham clash and Clara makes a bold move in her bid to outplay Sir Edward and Esther.