At the age of fifteen, she was accepted into the prestigious National Youth Theatre, and in 2001 began attending the Guildford School of Acting, where she graduated in 2004 with first class honours.

In addition, Stevenson served as an understudy to the roles of Winifred Banks and the title character Mary Poppins, and took part in the show's original cast recording.

In April 2008, she served as understudy to Jill Paice in the role of Scarlett O'Hara, in Sir Trevor Nunn's short-lived West End production of Gone with the Wind.

She began performances on 18 November, starring opposite Willemijn Verkaik, and later Kerry Ellis, Jennifer DiNoia and Emma Hatton in the role of Elphaba.

[2] Stevenson has credits in multiple workshops - Women on the Verge of a Nervous Breakdown as "Paulina", Pride and Prejudice as "Caroline Bingley", The Loved One as "Aimee", The Count of Monte Cristo as "Haydee", Moonlanding as "Pat Collins" and ‘Seance’ as Theresa (William’s Dead Wife).