Magellan studied History of Art at UEA and worked in London galleries for fifteen years. Since then, she has organised exhibitions, researched paintings and written articles, particularly on 19th- and 20th-century women artists. A contributor to the Oxford Dictionary of National Biography and BBC Woman’s Hour, she also works with charities supporting ex-offenders through art and education. Magellan's book, Utmost Fidelity, explores Marianne Stokes and her husband, the English landscape painter Adrian Stokes RA. She has recently lectured for the Art Fund, National Portrait Gallery, Pre-Raphaelite Society and Art Workers’ Guild, as well as the Art Society of Budapest. A Freeman of the Worshipful Company of Arts Scholars, she lectured for the Company at the Old Bailey in 2024 on Elizabeth Fry and her contribution over the past 200 years to prison reform through creativity, following the passing of the 1823 Gaols Act.