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Results found in several dictionaries: Collins, Collaborative Dictionary
costume drama 
  n 
  (=film) film  m  en costume d'époque 
(=play) 
pièce  f  en costume d'époque
  (=film genre) films  mpl  en costume d'époque 
(=dramatic genre) 
pièces  fpl  en costume d'époque

Collaborative Dictionary     English-French
verse drama n. la pièce de théâtre en vers Reverso General Dictionary 
agit prop drama n. le théâtre d'intervention Reverso General Dictionary 
nice suit n. le joli costume Reverso General Dictionary 
double-breasted suit n. le costume croisé Reverso General Dictionary 
pin-stripe suit n. le costume rayé Reverso General Dictionary 
***
'costume drama' also found in translations in French-English dictionary
école de théâtre nm. drama school Reverso General Dictionary 
bijou fantaisie pref. costume jewel Reverso General Dictionary 
pièce policière nm. crime drama Reverso General Dictionary 
costume de spectacle pref. costume Reverso General Dictionary 
costume d'époque pref. period costume Reverso General Dictionary 
costume folklorique pref. folk costume Reverso General Dictionary 
costume historique pref. historical costume Reverso General Dictionary 
costume régional pref. regional costume Reverso General Dictionary 
costume religieux pref. religious costume Reverso General Dictionary 
costume traditionnel pref. traditional costume Reverso General Dictionary 
bijouterie fantaisie nm. costume jewellery Reverso General Dictionary 
bijou de fantaisie pref. costume jewel Reverso General Dictionary 

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