Mary-Jannet Leith is a Scottish recorder player and researcher based in West London. After studying for both undergraduate and postgraduate research degrees in history at Oxford University, Mary-Jannet received a scholarship to study for a Master in Performance at the Royal College of Music. In 2014, she reached the Section Finals of the Royal Overseas League Competition and was selected for the Brighton Early Music Festival’s young artists’ scheme, BREMF Live! In 2016. In 2018, she won first prize in the ‘Solisten Instrumental’ category of the Internationaler Gebrüder-Graun-Wettbewerb, Bad Liebenwerda. Since 2018, with her duo partner Thomas Allery, she has been a Live Music Now musician, performing regularly to audiences who have little access to live classical music.

In 2019, Mary-Jannet founded Ensemble Hesperi with her colleagues Thomas Allery (harpsichord), Magdalena Loth-Hill (Baroque Violin) and Florence Petit (Baroque Cello). Through original research, Hesperi has gained a strong reputation for bringing forgotten musical stories to life. Inspired by research for the ensemble’s ACE-funded project "The Pheasant's Eye", Mary-Jannet embarked upon a PhD at the University of Southampton. Her doctoral research, supported by an AHRC studentship through the SWWDTP consortium, explores Scottish musical culture in eighteenth-century London; Hesperi’s 2021 project, “From Caledonia to the Capital”, supported by the Continuo Foundation, told the stories of Scottish composers who settled in eighteenth-century London. Further research led to Hesperi’s debut album, “Full of the Highland Humours”. In 2021, Mary-Jannet was awarded a Georgian Papers fellowship to study the role of music in the domestic lives of Georgian monarchs. Supported by a second grant from the Continuo Foundation and the Georgian Papers Programme, she created “Then I play’d upon the Harpsichord”, an immersive concert exploring the musical tastes and talents of Queen Charlotte, consort to George III.