After training at Studio 34, Dominique Massat entered the ‘classe libre’ section at Cours Florent, notably under the supervision of Michel Fau and Jean-Michel Rabeux, She then began working in the theatre under the direction of Frédéric Jessua in L’Atroce Volupté, by Max Maurey and Georges Neveux, Les Détraquées, by Olaf and Palau, Julius Caesar, by William Shakespeare, Gabegie, by Jean-François Mariotti, and The Misanthrope, by Molière. She was also directed by Isabelle Siou in Le Baiser de Sang, written by Jean Aragny and Françis Neilson, Igor Mendjisky in Hamlet, by William Shakespeare, Sébastien Rajon in The Balcony, by Jean Genet, Manon Savary in L’Illusion Comique, by Corneille, Olivier Quinzin in Andromaque, by Racine, Frédéric Ozier in The Bacchae, by Euripides, Armelle Legrand in Le Bonheur du Serpent by H. and V. Boulay, and The Park, by Botho Strauss.
She became part of Dramaticules in 2011. Since that time, she has performed in all their shows. She took over the role of Hérodias in Salomé, by Oscar Wilde (2010/11), and performed the role of Elisabeth, in Richard III, by William Shakespeare (2012/13), Mother Ubu, in L’Ubu roi des Dramaticules (2014/15), the Duchess and Dulcinee, in Don Quichotte (2015/16), Ophelia and Gertrude, in Hamlet (2018/19) and Blue Fairy and the Narrator in Pinocchio (2020/21).