In preparation for the title role, Esme Creed-Miles trained extensively with her dad Charlie Creed-Miles, a 20-year practitioner of martial arts.
In various scenes throughout the series Mireille Enos (Marissa) speaks fluent French, a skill she learned growing up in a home with a French mother.
Seasons 1 and 2 are set entirely in Europe and other places with NO connection to The United States (other than in occasional character dialogue) at all.