The 28-year-old, who plays Charlotte Haywood in the Jane Austen period drama, revealed that the series will look ahead to her character's growth while new pursuits are introduced.
WATCH: Charlotte returns to Sanditon in new series two trailer
Speaking to TV Insider, the star revealed: "My focus was to try and honour the Charlotte that was the Charlotte of episode one." She added: "And also come back fresh, with a bit more emotional experience and growth."
Charlotte was left heartbroken in the season one finale when Sidney Parker, played by Theo, decided to honour his word and marry Eliza Campion. The actor decided not to rejoin the series following its renewal.
Executive producer Susanne Simpson also told the publication: "We've heard from a lot of fans that they are going to greatly miss Sidney. What we hope is that they'll give the series a chance because this is really Charlotte's story."
Theo James is not returning to Sanditon
In one of the released trailers, Charlotte is meeting several dashing new bachelors who express an interest in her, and a character can be heard saying: "You can't recapture what you had with Sidney. Love isn't as simple as you seem to think."
The official synopsis explained: "The new series picks up the action nine months later, as the town grows in popularity, and features characters familiar and new. Charlotte takes up the role of governess to Augusta Wilson, Alexander Colbourne's ward and niece, who at the age of 17 pushes against authority and soon gives Charlotte a run for her money.
Rose's character Charlotte will have new love interests
"Charlotte's spirited younger sister, Alison Heywood comes to Sanditon to pursue her own romantic dream, and joined by The Parkers, the second series promises new romances, friendships and challenges for the residents as the Army makes Sanditon their new base.
"The Parkers are back, as Tom Parker strives to rebuild Sanditon. But there are many unforeseen issues awaiting him, while the secrets and lies of the dysfunctional Denhams continue to rock the foundations of the sunny seaside town. And, in her last summer season before turning 21, Georgiana Lambe, keen to forge her own identity, gets up to mischief in the name of love…but will she run the risk of being lonelier than ever before?"
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