Theatre credits include: The Secret Diary of Adrian Mole Aged 13 ¾ (Leicester Curve); Matilda The Musical (Cambridge Theatre); Coriolanus (Donmar Warehouse); Rags The Musical (Lyric Theatre); Peter Pan (The Dragon); Les Miserables (Queen’s Theatre); Oliver! (Theatre Royal Drury Lane/National tour); Joseph and his Technicoloured Dreamcoat, Chitty Chitty Bang Bang (New Theatre Oxford).
Sebastian also performed on stage at a charity concert with Emeli Sande and Laura Wright.
Television and film credits include: Music, War & Love, The Hippopotamus, Houdini and Doyle, Game of Thrones, Penny Dreadful.
Workshops include: The Braille Legacy (Colbert Entertainment Ltd.); Emil and the Detectives (National Theatre); I Can't Sing (SyCo Entertainment); Bumblescratch (Robert J. Sherman Productions); Nativity.