The core focus of this thesis is gender performance in two of Jane Austen’s novels, Pride and Prejudice and Emma, and twenty-first-century adaptations of these novels. The thesis revolves around six key texts: Austen’s novel Pride and Prejudice, its 2005 film adaptation of the same name directed by Joe Wright, and the transmedia modernisation, The Lizzie Bennet Diaries; as well as Austen’s novel Emma, its 2020 film adaptation of the same name directed by Autumn de Wilde, and the transmedia web series, Emma Approved. There have undoubtedly been shifts in gender performance over the two hundred years since Austen published her novels, but these are not always reflected in the adaptations. In part this is due to the surprisingly progressive nature of some of Austen’s meditations on gender, with Elizabeth Bennet from Pride and Prejudice presenting as a pre-feminist and George Knightley from Emma performing as a pre-feminist man. These aspects of gender performance are extended by Keira Knightley’s portrayal of Elizabeth Bennet in Wright’s film, which reframes the character as a Romantic feminist, and Johnny Flynn’s performance of Mr. Knightley as a hero positioned under the female gaze in de Wilde’s film. Yet, the thesis also reveals that Austen’s feminist precursors are not always developed in contemporary adaptations. Indeed, Lizzie Bennet in The Lizzie Bennet Diaries is a postfeminist who is far from being an autonomous twenty-first century woman and is dependent on family and male suitors to provide her with opportunities. Likewise, the opportunity to reimagine Austen’s characters in a twenty-first-century gender context is also ignored in some adaptations, particularly the transmedia web series, with Emma in Emma Approved continuing to endorse patriarchal structures in the same way that she does in Austen’s original novel. The dandyism of Frank Churchill in Austen’s Emma is also undercut in Emma Approved through a performance of heteronormativity that sidelines the queer potential initiated by previous adaptations, such as the 1995 film Clueless. Most striking is the stagnant gender performance of Mr. Darcy from Pride and Prejudice who remains the embodiment of hegemonic gentry masculinity in both the film and the web series. This thesis reveals that the lack of change in gender performance in some contemporary Austen adaptations demonstrates the persistence of hegemonic masculinity in the twenty-first century, while postfeminist performances of gender at times seem regressive.