Isabella Briggs joined The Summer I Turned Pretty season 3 as a new series regular alongside Kristen Connolly.
The casting announcement expanded the regular ensemble for the show’s final season. Briggs and Connolly were reported as new series regulars, while several other performers, including Sofia Bryant and Lily Donoghue, were announced in recurring capacities.
That distinction matters because “series regular” and “recurring” describe different billing categories. Briggs was part of the regular cast group, whereas the other newly announced performers were not all assigned the same status.
Briggs’s casting was announced before the season premiered in July 2025. The season ultimately ran for 11 episodes and served as the television adaptation’s concluding season.