Spencer-Longhurst joined the National Youth Music Theatre at age eleven, and subsequently studied at Manchester University.
Her professional stage debut was in 2007 at the Young Vic Theatre in a critically acclaimed production of The Member of the Wedding where she played the part of Frankie Addams.
[2][3] She played Rosalie in the Lillian Helman play The Children's Hour at The Royal Exchange Theatre, Cecily in a musical adaptation of Oscar Wilde's The Importance of Being Earnest,[4][5] and had also performed the role of Belle in a stage version of A Christmas Carol at the King's Head Theatre.
In addition, she had roles as Reza in the West End production of the musical Once and Lavinia in Titus Andronicus at Shakespeare's Globe.
[7] Her motion picture debut Walking with the Enemy had won her a Best Supporting Actress award at the Fort Lauderdale International Film Festival and was released in April 2014.