Ruby Barnhill as Princess Emmy (voice)

Franka Potente as Queen Karla (voice)

John Hannah as King Karl (voice)

Tim McInnerny as Gregorius the Ghost (voice)

Bella Ramsey as Princess Gizana (voice)

Kenny Blyth as Additional Voices

Uwe Ochsenknecht as Vincenzo Massimo Cerimonata (voice)

Tyler Collins as Additional Voices

Michael Daviot as Xaver (voice)

Joel Fry as Ceasar (voice)

Christina Gordon as Additional Voices

Al Hawkinson as Paul (voice)

Robert Jack as Sebastian April (voice)

Nathan Mack as David (voice)

Scarlett Mack as Additional Voices

Steven McNicholl as Vincenzo (voice)

Euan Mitchell as Moritz (voice)

James Anthony Pearson as Donny / Valentine (voice)

Gabriel Quigley as Frau Zwickelmeier / Daphne (voice)

Vari Sylvester as Marie (voice)

Claire Waugh as Fionnuala Bloom (voice)